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msjint40.dll is the Microsoft Jet 4.0 Database Engine International DLL. If Windows says msjint40.dll is missing, the affected program is usually an older database application, installer, or Access-compatible tool that expects the 32-bit Jet database provider.
Do not download a replacement DLL from a random website and copy it into System32. The safer fix is to identify the program that needs Jet, repair or reinstall that program, then repair Windows components if the file itself has been removed or corrupted.
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What msjint40.dll does
Microsoft Jet 4.0 is a legacy database engine used by applications that work with Microsoft Access .mdb databases. Programs commonly connect to it through the provider named Microsoft.Jet.OLEDB.4.0.
msjint40.dll is one supporting file in that older database stack. It is not:
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- A Visual C++ runtime file
- A DirectX component
- A graphics or sound driver
- A game-specific library
- The main Jet engine file,
msjet40.dll - The related Jet transaction file,
msjter40.dll - A modern Access Database Engine, also called ACE
Microsoft identifies the file as the Microsoft Jet Database Engine International DLL. It is a 32-bit x86 component. On 64-bit Windows, 32-bit system files are normally found under C:WindowsSysWOW64; on 32-bit Windows, they are normally under C:WindowsSystem32. This naming is counterintuitive: System32 does not mean that every file in it is 32-bit.
Jet is legacy technology, and its installation history varies between Windows generations and application packages. Older software could install Jet through products such as Office, Visual Studio, or its own setup process rather than receiving it as a guaranteed part of every Windows installation.
Messages this guide covers
Users report several variants of the same underlying problem:
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Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minute- “The program can’t start because msjint40.dll is missing from your computer.”
- “There was a problem starting msjint40.dll. The specified module could not be found.”
- “Error loading msjint40.dll.”
- “The code execution cannot proceed because msjint40.dll was not found.”
- “msjint40.dll is either not designed to run on Windows or it contains an error.”
These are common reported messages, not an official exhaustive list. The exact wording matters less than which program displays it and when the error began.
Fix 1: Repair or reinstall the affected program
Time needed: 5–20 minutes
This is the most likely fix when only one application reports the missing file. The program may have lost part of its installation during an update, uninstall, failed repair, antivirus action, or disk problem.
Use Windows repair options
- Press
Windows + Ito open Settings. - Select Apps.
- Select Installed apps on Windows 11, or Apps & features on Windows 10.
- Find the program that displays the error.
- Select the three-dot menu beside it on Windows 11, or select the program on Windows 10.
- Choose Advanced options if available.
- Select Repair.
- Launch the program again.
If there is no Repair option, open the program’s own launcher or maintenance utility. Look for Repair, Verify files, Scan and repair, or Restore installation.
The repair worked if the application starts without the msjint40.dll message and can open its database normally.
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 errorsIf the error remains, uninstall the application, restart Windows, and reinstall it from its original vendor media or official installer. Back up the program’s database files first. An application reinstall remains the definitive fix when that application owns a private copy of the Jet components or expects a specific installation layout.
Do not copy a DLL from another computer unless the application vendor specifically documents that procedure. A file can have the right name but the wrong version, architecture, language resources, or dependencies.
Fix 2: Check antivirus quarantine
Time needed: 5 minutes
Security software can quarantine a file after a detection or a failed update. That does not prove that msjint40.dll is malware, and the missing-file message alone is not evidence of infection.
- Open Windows Security from the Start menu.
- Select Virus & threat protection.
- Select Protection history.
- Review recent actions involving the affected application or Jet files.
- If the file was quarantined, inspect its original path and detection details.
- Restore it only when the file is clearly Microsoft-signed, the path matches the expected Windows or application location, and you have established that the detection is false.
- Add an exclusion only for a trusted application folder when the vendor’s support instructions justify it.
If the file was removed from a Windows directory, do not simply restore it and stop there. Run the Windows repair steps below. If the file was part of the application directory, repair or reinstall the application instead.
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Time needed: 15–45 minutes
This fix applies when the file is missing from the expected Windows directory, several programs are failing, or the problem started after a failed update or system change.
Install pending updates
- Press
Windows + I. - Open Windows Update.
- Select Check for updates.
- Install all available updates.
- Restart when Windows requests it.
- Check for updates again after the restart.
Updates can restore or service compatibility components, but Windows Update does not guarantee that every old Jet application will become compatible.
Run DISM
DISM repairs the Windows component store, which can provide the source files needed by System File Checker.
- Open the Start menu.
- Type
Command Prompt. - Right-click Command Prompt.
- Select Run as administrator.
- Approve the User Account Control prompt.
- Run this command:
DISM.exe /Online /Cleanup-Image /RestoreHealth
- Wait for the operation to finish. Do not close the window because progress may pause for a while.
- Restart Windows if DISM reports that a restart is required.
Run System File Checker
Open an elevated Command Prompt again and run:
sfc /scannow
Wait until verification reaches 100 percent. Then restart Windows and test the application.
Success means SFC reports that it repaired corrupted files, or the program starts normally after the scan. If SFC reports that it found no integrity violations, the problem may belong to the application installation or the 32-bit provider configuration rather than a damaged protected Windows file.
SFC does not always repair this specific DLL. It repairs protected files only when the file belongs to the installed component set and a valid repair source is available.
If you are tired of repeating DISM and SFC while hunting through repair logs, Outbyte PC Repair can scan for system problems and show what it found; its full version performs repairs, but it is not required and reinstalling the affected Jet application remains the definitive fix when the application installation is the damaged part.
If DISM cannot find repair files
If DISM reports that source files could not be found, Microsoft documents using a matching Windows installation source with /Source and /LimitAccess. The source must match the installed Windows edition and build closely enough to supply valid component files. Do not point DISM at a random ISO or another computer’s Windows directory.
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Fix 4: Check the file’s path, signature, and architecture
Time needed: 5–10 minutes
Use this step to distinguish a missing Windows component from a bad application copy.
- Open File Explorer.
- Check
C:WindowsSysWOW64on 64-bit Windows. - Check
C:WindowsSystem32on 32-bit Windows. - Search for
msjint40.dllfrom This PC if it is not in the expected location. - Right-click any result and select Properties.
- Open the Details tab.
- Confirm that the description identifies the Microsoft Jet Database Engine International DLL and that the company is Microsoft Corporation when those fields are present.
- Open the Digital Signatures tab.
- Select the Microsoft signature and choose Details.
- Confirm that Windows reports the signature as valid.
A legitimate file should also have a location that makes sense. A copy in a random temporary folder, a user profile’s downloads directory, or an unrelated game folder deserves extra scrutiny.
Known records show multiple historical builds, including 32-bit versions 4.0.9635.0, 4.0.9502.0, and 4.0.8905.0. Microsoft servicing records also document other x86 builds, including 4.0.9801.1. These are historical observations, not a universal version requirement. Do not replace a working file merely because its version differs from an online listing.
The related msjint40.dll.mui file is a language-resource file. It is not a replacement for the executable DLL.
Fix 5: Resolve the 32-bit versus 64-bit problem
Time needed: 10–30 minutes
Jet 4.0 is 32-bit only. A 32-bit application can use it on 64-bit Windows through Windows compatibility support, but a 64-bit application cannot load the 32-bit Jet provider directly.
This often happens after an application upgrade, when an old 32-bit program is replaced by a newer 64-bit executable, or when a database utility launches the wrong executable.
Check the application’s documentation or installation folder for separate executables. If both are available, launch the 32-bit build. A vendor may label it x86, 32-bit, or place it in a separate program folder.
If the program specifically requires Microsoft.Jet.OLEDB.4.0, do not assume that installing the Microsoft Access Database Engine 2016 Redistributable will solve it. ACE and Jet are different providers. A durable solution may require a vendor update, a supported 32-bit runtime environment, or migration to a provider that the application supports.
A provider error such as “Microsoft.Jet.OLEDB.4.0 provider is not registered” is not necessarily a missing msjint40.dll problem. It usually points to provider registration, application architecture, permissions, or connection-string configuration.
Fix 6: Update the application and relevant drivers
Time needed: 10–30 minutes
Drivers are not the normal source of msjint40.dll, but an old application can fail after a broader system change. Update the application first, then check chipset, storage, and other hardware drivers if Windows has also shown device or disk errors.
Check Windows optional driver updates
- Press
Windows + I. - Open Windows Update.
- Select Advanced options.
- Select Optional updates.
- Expand Driver updates.
- Install only drivers appropriate for your hardware.
- Restart Windows.
Check Device Manager
- Right-click the Start button.
- Select Device Manager.
- Expand categories such as Storage controllers, IDE ATA/ATAPI controllers, and System devices.
- Right-click a relevant device.
- Select Update driver.
- Choose Search automatically for drivers.
- Restart if a driver is installed.
Do not use Device Manager to hunt for a Jet DLL. Drivers do not replace database engine files.
If checking dozens of hardware drivers manually is the frustrating part, Outbyte Driver Updater can scan and identify stale drivers; its free scan shows the findings, while driver installation is handled by the full version, and it is not required for a normal Jet repair.
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regsvr32 is for registering DLL command components that expose a registration entry point such as DllRegisterServer. It is not a general DLL repair tool.
There is no evidence that msjint40.dll is an ActiveX or COM registration DLL. Running this command is therefore likely to produce an entry-point error:
regsvr32 msjint40.dll
It will not restore a deleted file, repair a damaged component store, install the Jet provider, or fix a 32-bit/64-bit mismatch. Use the application installer, Windows Update, DISM, and SFC instead.
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Fix 7: Use System Restore or repair Windows
Time needed: 30 minutes to several hours
Use System Restore when the error began immediately after a driver installation, application removal, update, or other identifiable system change.
- Press
Windows + I. - Select System.
- Select Recovery.
- Choose Open System Restore where available.
- Select a restore point dated before the problem began.
- Review the affected programs and drivers.
- Start the restore and let Windows restart.
System Restore does not normally delete personal documents, but it can remove applications or drivers installed after the selected restore point.
If restore points are unavailable or the repair repeatedly fails, back up important files and consider an in-place Windows repair using matching official Windows installation media. If disk errors, repeated component corruption, or failed repairs continue, check drive health before performing more repairs.
Common causes and the matching fix
| Likely cause | Best response |
|---|---|
| Incomplete or damaged application installation | Repair or reinstall the affected application |
| Deleted or corrupted Windows component | Windows Update, DISM, then SFC |
| Antivirus quarantine | Verify the signature and restore only a trusted file |
| 32-bit application using the wrong build | Use the vendor’s 32-bit executable or supported migration |
| Disk or file-system corruption | Back up data, check drive health, then use recovery options |
| Obsolete Jet-dependent software | Update the vendor software or use a supported 32-bit environment |
Avoid random DLL downloads
Standalone DLL download sites can provide the wrong version, wrong architecture, wrong language resource, or a tampered file. Even a genuine-looking copy may not match the Jet components already installed, and copying it into System32, SysWOW64, or an application folder can hide the actual installation problem.
Use the affected program’s official installer, original installation media, Windows Update, DISM, and SFC. If the program is too old for current Windows architecture or provider requirements, contact its developer rather than forcing an unrelated DLL into the system.
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FAQ
Is msjint40.dll a Windows file?
It is a Microsoft Jet component, but its presence depends on the Windows installation, legacy compatibility components, and software that installed or uses Jet. It should not be treated as a guaranteed file on every Windows 10 or Windows 11 installation.
Is msjint40.dll safe?
A file with the expected Microsoft metadata, valid Microsoft signature, and expected Windows or application path is consistent with the Jet component. A random copy in a temporary or download folder should not be trusted solely because its filename matches.
Why does a 32-bit DLL work on 64-bit Windows?
64-bit Windows can run many 32-bit applications through its compatibility layer. Those applications use 32-bit components from the 32-bit system environment, normally SysWOW64. A 64-bit application cannot directly load the 32-bit Jet provider.
Will reinstalling Visual C++, DirectX, or .NET fix it?
Normally no. Those packages are separate runtime families and do not restore Microsoft Jet 4.0. Repair the affected application or Windows component store instead.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
Should I install ACE as a replacement?
Not automatically. Access Database Engine, or ACE, is different from Jet 4.0. Install or migrate to ACE only when the application vendor supports that provider and the application’s architecture is compatible.
What if the program still fails after SFC?
Reinstall or repair the application, confirm that it uses a 32-bit executable, and check whether the error is actually a provider-registration message. If the issue began after a system change, try System Restore. Persistent DISM failures may require a matching repair source or an in-place Windows repair.
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