ucproxysdk.dll is missing. Windows may also report that ucproxysdk.dll was not found, could not be loaded, or caused an application error.
This file belongs to the Windows desktop edition of UC Browser, developed by UCWeb. It is not a Windows component, Microsoft runtime, DirectX file, or general-purpose system DLL. The safest repair is to restore the complete UC Browser installation rather than downloading the DLL separately.
As an Amazon Associate I earn from qualifying purchases.
Which fix applies to you
Choose the situation that best matches what happened:
Recommended Free Tools
- UC Browser stopped starting after an update or reinstall: repair or reinstall UC Browser first.
- The file disappeared after an antivirus alert: check Windows Security Protection history before restoring anything.
- You copied browser files from another computer or installation: remove the mixed files and reinstall the complete matching release.
- The error says “entry point not found” or
0xc000007b: suspect a version or architecture mismatch. - Several unrelated programs have DLL errors: repair Windows components with DISM and SFC.
- You installed UC Browser from an unofficial package: scan Windows and replace the package with software from the official UC Browser PC download page.
- The error names another file, such as
VCRUNTIME140.dll: repair that named dependency instead of treatingucproxysdk.dllas a Microsoft runtime.
Where ucproxysdk.dll normally belongs
Historical UC Browser installations place the file in the browser’s own application directory, beside files such as UCBrowser.exe and other browser components. Examples include folders under:
#1 Best Overall
- POWER YOUR STUDY, FUEL YOUR PLAY – Discover smarter learning with the Lenovo Idea Tab. Stay campus-ready with all-day battery life, AI-powered apps to enhance your work, and sharp graphics for tv marathons with friends.
- SMOOTH, POWERFUL, IMMERSIVE – The MediaTek Dimensity 6300 processor is more powerful than ever, with the AI-enhanced multitasking you need to stay ahead.
- CIRCLE IT, SEARCH IT – Use your Lenovo Tab Pen or fingertip to circle items for instant search results or to translate other languages without switching apps. Circle to Search with Google ensures answers are only a circle away.
- SHARP VIEW, CLEAR SOUND – Experience sharp visuals and immersive sound for study sessions and streaming breaks. With 72% NTSC and quad Dolby Atmos-tuned speakers you can enjoy your study breaks with vivid videos and crystal-clear sound.
- LEVEL UP YOUR STUDY – Write, organize, sketch, and calculate with four learning apps built to match your flow. Lenovo AI Note, Squid, Nebo, and MyScript Calculator help you stay clear, focused, and ready for every study session.
C:Program FilesUCBrowserApplication
C:Program Files (x86)UCBrowserApplication
The exact subfolder depends on the installed UC Browser release. The file should normally remain inside the UC Browser application folder. There is no evidence that it belongs in either of these Windows folders:
C:WindowsSystem32
C:WindowsSysWOW64
Do not move it to those locations. System32 is not a universal destination for missing DLLs, and placing an application-private file there can create further version, security, and loading problems.
Fix 1: Repair or reinstall UC Browser
This is the most likely solution because ucproxysdk.dll is an application-local component.
The Tool Desk
Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Try Windows repair first
- Press Windows + I to open Settings.
- Select Apps.
- Choose Installed apps on Windows 11, or Apps & features on Windows 10.
- Find UC Browser.
- Select the three-dot menu on Windows 11, or select the program and choose Advanced options where available.
- Choose Repair if Windows provides that option.
- Start UC Browser again.
If the error remains, uninstall the affected copy:
- Open Settings > Apps > Installed apps.
- Select UC Browser.
- Choose Uninstall and follow the prompts.
- Restart Windows.
Before uninstalling, preserve bookmarks or profile data if you still need it. Old browser builds may store user data inside their installation or profile directories, so do not delete folders blindly until you have checked for personal data.
Install a clean copy
Download UC Browser only from UCWeb’s official UC Browser PC download page. Do not use a DLL-only download page or an unofficial repacked installer.
Run the installer, allow it to complete, and restart Windows if requested. Then launch the browser from its new shortcut.
A successful repair usually means that UC Browser opens without the missing-file dialog. If the same message returns immediately after a clean installation, note whether the installer completed normally and continue with the antivirus and security checks below.
Free tools Windows power users keep installed
One-click scans. No signup required.
Rank #2
- COMPACT SIZE, COMPACT FUN – The Lenovo Tab One is compact, efficient, and provides non-stop entertainment everywhere you go. It’s lightweight and has a long-lasting battery life so the fun never stops.
- SIMPLICITY IN HAND - Add a touch of style with a modern design that’s tailor-made to fit in your hand. It weighs less than a pound and has an 8.7” display that’s easy to tuck in a purse or backpack.
- NON-STOPPABLE FUN – Freedom never felt so sweet with all-day battery life and up to 12.5 hours of unplugged YouTube streaming. It’s designed to charge 15W faster than previous models so you can spend less time tethered to a power cable.
- PORTABLE MEDIA CENTER - Enjoy vibrant visuals, immersive sound, and endless entertainment anywhere you go. The HD display has 480 nits of brightness for realistic graphics and dual Dolby Atmos speakers that provide impressive sound depth.
- ELEVATED EFFICIENCY - Experience the MediaTek Helio G85 processor and 60Hz refresh rate that ensure fluid browsing, responsive gaming, and lag-free streaming.
Do not combine ucproxysdk.dll from one UC Browser release with UCBrowser.exe from another. Reinstall the entire application so its executable, DLLs, browser resources, and dependent libraries come from the same package.
Fix 2: Check whether antivirus quarantined the file
Security software may have removed or renamed the DLL. This can happen with old browser builds or unofficial and repacked installers. A legitimate-looking filename does not prove that a quarantined copy is safe.
In Microsoft Defender:
- Open Start and search for Windows Security.
- Open it and select Virus & threat protection.
- Select Protection history.
- Review recent detections involving UC Browser or
ucproxysdk.dll. - Expand a detection to see its location, threat name, and action.
- Do not choose Restore merely because UC Browser now reports the file as missing.
If the browser came from an unofficial source, remove it and perform a full scan instead:
- Open Windows Security.
- Select Virus & threat protection.
- Choose Scan options.
- Select Full scan.
- Choose Scan now.
Microsoft’s quarantine guidance explains the restoration workflow. Restore the file only after investigating the detection and confirming that the complete browser installation came from a trustworthy source. If Defender removes it again, do not create a permanent exclusion. Scan the installer and replace the browser package.
Fix 3: Replace mixed or incompatible browser files
A file can exist and still fail to load. This commonly happens after copying files between computers, restoring an old browser directory, or combining files from different UC Browser releases.
Possible symptoms include:
- An entry-point error
- An application crash
0xc000007b- A message that the file is not designed to run on Windows
- UC Browser opening briefly and then closing
The Program Files and Program Files (x86) locations can provide clues about how an installation was arranged, but the folder alone does not prove the DLL’s architecture. A 32-bit DLL should not be copied into a 64-bit application installation, and a 64-bit application should not be repaired with files from an unrelated 32-bit release.
The correct procedure is:
- Uninstall UC Browser.
- Restart Windows.
- Remove only leftover UC Browser program files after preserving personal data.
- Download a complete installer from UCWeb’s official PC page.
- Install the browser without copying individual DLLs from another machine.
- Test the new installation.
If the error changes from “missing” to “entry point not found,” that strongly suggests the DLL and executable do not belong to the same release. Replace the complete installation rather than searching for another copy of the DLL.
Rank #3
- 【Dual-Function 2-in-1 Tablet】URAO Android 16 Tablet is a game-changer with 2-in-1 professional work mode. The tablet is compatible with a Bluetooth keyboard, mouse, stylus, headset, and a convenient foldable case. The setup and connection process is straight forward, enabling you to effortlessly transform your tablet into either a laptop or a computer mode. Friendly Tips: Mouse does not come with batteries.
- 【Android 16 & Octa-Core Processor】URAO Android tablet features the latest operating system Android 16 and an 1.8 GHz octa-core processor ensure of excellent performance, seamless multitasking, getting rid of annoying ads, emphasizing privacy and security by designing enhanced app permissions, providing you complete management control.
- 【36GB (6+30GB) RAM 128GB ROM 】Our 11 inch tablet comes with 36GB (6+30GB) RAM 128GB ROM and maximun 1TB TF card ( not included )expandable ensures you of a fast APP launch and smooth gaming experience. URAO tablet also come with pre-installed Google Play Store, you can easily download any needed Apps such as Facebook, Twitter, Youtube, etc.
- 【7800mAh Battery with Fast Charge】The built-in large capacity and low consumption CPU enable our URAO 11 inch tablet to stand by for up to 3 days and allows you to enjoy up to 8 hours of mixed reading, watching TV shows, playing games, surfing the web. URAO tablet adopts fast-charging technology ,easily charge via the USB Type-C port and rest assured the battery will last. It is a good companion for you to play and study!
- 【Wi-Fi 6+Bluetooth5.4】URAO 11 inch android tablet adopts the lastest sixth generation WiFi technology and the upgraded bluetooth 5.4. Dual band integrated chips make the 5g WiFi and 2.4g WiFi more stable and the lastest bluetooth 5.4 connection supports all your favorite accessories, highly increased the speed of data transfer, improved network capacity and reduced network delays.
Fix 4: Check the error’s actual dependency
A missing ucproxysdk.dll message may appear while another dependency is also damaged. Read the complete dialog carefully. If it names a different file, repair that file’s application or runtime instead.
Visual C++, DirectX, and .NET
Do not reinstall Visual C++, DirectX, or .NET solely because ucproxysdk.dll is missing. There is no evidence that this UC Browser component is supplied by Microsoft’s Visual C++ Redistributable.
If the dialog specifically names a Microsoft runtime, use Microsoft’s supported Visual C++ Redistributable packages. Install the architecture named by the affected application, then restart Windows and test again.
Likewise, install or repair DirectX or .NET only when Windows or the application explicitly identifies one of those components. Reinstalling unrelated runtimes will not recreate an application-private UC Browser DLL.
Fix 5: Repair Windows components when other programs also fail
Windows repair commands are useful when many unrelated applications report damaged system files. They normally will not recreate ucproxysdk.dll, because that file belongs to UC Browser rather than Windows.
Outdated Drivers Are Slowing You Down
One free scan finds every outdated or missing driver and matches the right update for your exact hardware.Free scan · exact hardware matchPC Slower Than It Used to Be?
A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11- Open Start.
- Search for Command Prompt.
- Right-click it and select Run as administrator.
- Run this command:
DISM.exe /Online /Cleanup-image /Restorehealth
- Wait for it to finish.
- Then run:
sfc /scannow
- Wait until verification reaches 100 percent.
- Restart Windows.
Microsoft explains this sequence in its System File Checker guidance. After restarting, test UC Browser. If only UC Browser still fails, return to the clean reinstall rather than repeating SFC indefinitely.
When manually running DISM and SFC becomes difficult, Outbyte PC Repair can scan for the issues involved and show what needs attention; repairs are performed by the full version. Reinstalling UC Browser remains the definitive fix for this application-specific DLL.
Fix 6: Update drivers only when the evidence points there
A graphics or device driver is not the usual cause of one missing UC Browser DLL. Consider driver work only if UC Browser crashes after opening, the error names a graphics component, or other applications show display-related failures.
Rank #4
- 【Android 16 OS & High-Performance CPU】 Evermyth GMS-certified tablet runs on the Android 16 operating system, allowing direct downloads of popular apps from the Play Store. Powered by a robust 5-core processor that hits speeds up to 1.8GHz, the android tablet is engineered to boost multitasking performance. Whether you’re working, watching videos, or gaming, this 5-core tablet pc operates seamlessly, delivering a fast, professional-grade experience.
- 【24GB RAM + 64GB ROM + 1TB Expandable Storage】 Our 10 inch electronics tablets comes with 24GB RAM (3GB physical + 21GB virtual), 64GB ROM, and supports up to 1TB of expandable storage via a TF card (not included). This ensures quick app launches and smooth gameplay.
- 【10 inch HD IPS In-Cell Display】 This tablet PC boasts a 1280×800 high-resolution IPS screen that delivers vibrant, true-to-life colors. Enjoy sharper, brighter visuals for a more immersive viewing experience. The 5MP front and 8MP rear camera can handle video calls and photo recording with ease. LCD touchscreen uses low-blue-light tech to cut down on eye strain from screen flicker and harsh blue light. Slim and lightweight, this 10-inch tablet amps up immersion for all your favorite activities.
- 【6000mAh Rechargeable Battery】 Electronics tablets Packed with a 6000mAh battery and a low-power-consuming CPU, Evermyth 10 inch tablet offers up to 3 days of standby time and up to 8 hours of mixed usage—perfect for reading, streaming, or web browsing. Charging is a breeze via the USB-C port, making the tablet an ideal companion for both entertainment and work!
- 【Wi-Fi 6 & Bluetooth 5.4】 Evermyth Android 16 tablet features the latest Wi-Fi 6 and upgraded Bluetooth 5.4. It supports dual-band (5GHz/2.4GHz) Wi-Fi connectivity for stable, high-speed transfers. Bluetooth 5.4 ensures seamless compatibility with all your favorite accessories.
To check drivers:
- Right-click Start.
- Select Device Manager.
- Expand the relevant category, such as Display adapters.
- Right-click the device.
- Select Update driver.
- Choose Search automatically for drivers.
- Restart Windows if a driver is installed.
You can also select Properties > Driver to review the provider and date. Do not replace drivers randomly in response to a simple missing-DLL dialog.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
If identifying stale drivers across multiple devices is taking repeated manual checks, Outbyte Driver Updater can scan and identify driver problems; driver installation is performed by the full version. This does not replace reinstalling UC Browser when the failure is confined to that program.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Why regsvr32 usually does not apply
regsvr32 is intended for DLLs that provide registration functions such as DllRegisterServer. An application-private runtime library loaded directly by its executable does not normally need registration.
Running this command is therefore unlikely to repair UC Browser:
regsvr32 UCProxySDK.dll
It may produce an error stating that the entry point was not found or that DllRegisterServer failed. Do not register the file unless a verified UCWeb installer or support instruction specifically requires it. A missing or mismatched application DLL is repaired by restoring the complete application, not by adding a registry entry.
Never download the DLL by itself
Random DLL download sites are unsafe for this problem. A replacement may contain malware, belong to a different UC Browser release, use the wrong architecture, or lack dependent files required by the executable. It may also hide the reason antivirus removed the original file.
The safe sources are:
- The official UC Browser PC installer from UCWeb
- An intact copy inside the same trusted installer, matching the exact release
- A repair or reinstall function supplied by the software package
Even in the rare case where manual recovery is unavoidable, place a trusted matching copy back into the original UC Browser application folder, not into System32 or SysWOW64.
If reinstalling UC Browser still fails
Work through this escalation list:
- Confirm that the error still names
ucproxysdk.dlland not another dependency. - Check Windows Security Protection history again.
- Remove leftover UC Browser program files after backing up personal data.
- Restart Windows and install a clean official package.
- Test from a new Windows user account. If it works there, the original browser profile or permissions may be damaged.
- If UC Browser was bundled with another program, use that program’s Repair, Verify files, or reinstall function.
- Run a full Microsoft Defender scan if the installer was unofficial or repeatedly triggers detections.
- Consider System Restore only if the file disappeared after a recent system-wide change and no clean installer is available.
- If the official installer itself will not run, check whether the Windows installation is old or unsupported and consider using a maintained browser.
FAQ
Is ucproxysdk.dll part of Windows?
No. It is associated with the Windows desktop edition of UC Browser and should remain in the browser’s application directory.
Best Value
- Do what you love, uninterrupted — 25% faster performance than the previous generation and is ideal for seamless streaming, reading, and gaming.
- High-def entertainment — A 10.1" 1080p Full HD display brings brilliant color to all your shows and games. Binge watch longer with 13-hour battery, 3 or 4 GB RAM, 32 or 64 GB of storage, and up to 1 TB expandable storage with micro-SD card (sold separately).
- Thin, light, durable — Tap into entertainment from anywhere with a lightweight, durable design and strengthened glass made from aluminosilicate glass. As measured in a tumble test, Fire HD 10 is 2.7 times as durable as the Samsung Galaxy Tab A8 (2022).
- Stay up to speed — Use the 5 MP front-facing camera to Zoom with family and friends, or create content for social apps like Instagram and TikTok.
- Ready when inspiration strikes — With 4,096 levels of pressure sensitivity, the Made for Amazon Stylus Pen (sold separately) offers a natural writing experience that responds to your handwriting. Use it to write, sketch in apps like OneNote, and more.
Can I copy it into System32?
No. That does not repair the UC Browser installation and can create an incorrect system-wide copy.
Quick wins for a faster PC:
Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Is the file automatically safe because UC Browser needs it?
No. Historical UC Browser packages, including repacked distributions, have appeared in security research. Source and antivirus results matter more than the filename.
Should I restore it from quarantine?
Only after investigating the detection and confirming the installer’s source. A missing file is not evidence of a false positive.
Do I need to install Visual C++?
Only if the actual error names a Visual C++ runtime such as VCRUNTIME140.dll or MSVCP140.dll. ucproxysdk.dll itself is not established as a Microsoft runtime file.
What does 0xc000007b mean here?
It can indicate mixed 32-bit and 64-bit files or a damaged dependency. Reinstall the complete matching UC Browser package instead of copying individual DLLs.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errorsAre published hashes or version numbers definitive?
No. Third-party indexes may report metadata, but those values are not authoritative identification from UCWeb or Microsoft. Use a complete installer from the official source.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
