How to Fix Unidrv.dll Not Found or Missing Errors

Unidrv.dll errors are caused by situations that lead to the removal or corruption of the unidrv.dll file, a DLL file associated with Microsoft's Universal Printer Driver.

It's normally stored in a System32 folder or another Windows system folder:

C:\Windows\System32\spool\drivers\x64\
C:\Windows\System32\DriverStore\FileRepository\
C:\Windows\WinSxS\

In some cases, unidrv.dll errors could indicate a registry problem, a virus or malware issue, or even a hardware failure.

Unidrv.dll Errors

There are several ways unidrv.dll errors can show up on your computer. Here are some of the more common error messages you might see:

• Unidrv.dll Not Found
• This application failed to start because unidrv.dll was not found. Re-installing the application may fix this problem
• Cannot find [PATH]\unidrv.dll
• The file unidrv.dll is missing
• Cannot start [APPLICATION]. A required component is missing: unidrv.dll. Please install [APPLICATION] again

The context of the error is an important piece of information that will be helpful while solving the problem. Unidrv.dll error messages might appear while using or installing certain programs, when Windows starts or shuts down, or maybe even during a Windows installation.

How to Fix Unidrv.dll Errors

Follow these steps in the order they're given below to try the simpler solutions first.

1. Restore unidrv.dll from the Recycle Bin. The easiest possible cause of a "missing" unidrv.dll file is that you've mistakenly deleted it.

   If you suspect this, but you've already emptied the Recycle Bin, you may be able to recover the file with a free file recovery program.

   Start Windows in Safe Mode to complete any of these steps if you're unable to access Windows normally due to the error.

2. Run a virus/malware scan of your entire system. Some unidrv.dll errors could be related to a virus or other malware infection on your computer that has damaged the DLL file. It's even possible that the unidrv.dll error you're seeing is related to a hostile program that's masquerading as the file.

3. Use System Restore to undo recent system changes. If you suspect that the unidrv.dll error was caused by a change made to an important file or configuration, System Restore could solve the problem.

4. Run the sfc/scannow System File Checker command to replace a missing or corrupt copy of the unidrv.dll file. Since this DLL file is provided by Microsoft, the System File Checker tool should restore it.

5. Install any available Windows updates. Many service packs and other patches replace or update some of the hundreds of Microsoft distributed DLL files on your computer. The unidrv.dll file could be included in one of those updates.

6. Update the printer drivers. Since the unidrv.dll file is associated with Microsoft's printer driver, updating it should fix any "unidrv.dll is missing" or related errors.

   Probably the easiest way to install a print driver is to first complete any pending Windows updates (Step 5), but using a driver updater tool could be useful, too.

7. Extract unidrv.dll from its original source, the CAB file. There's a CAB file in Windows XP where the unidrv.dll file is copied from when Windows is first installed. Open this file, and you'll be able to pull the unidrv.dll file from it and put it wherever the error message says the file is missing from.

   To do this, open the C:\Windows\Driver Cache\i386\ folder and look for a service pack CAB file, like sp3.cab if XP is updated to service pack 3. Open the CAB file with 7-Zip and then copy the unidrv.dll file out of it.

   It seems that unidrv.dll error messages are more common on Windows XP, but if you're seeing one in a newer version of Windows, use Everything to search for a copy of unidrv.dll elsewhere on the computer that you can copy to where it needs to be.

8. Reinstall the program that uses the unidrv.dll file. If the unidrv.dll DLL error occurs when you use a particular program, reinstalling the program should replace the file.

9. Roll back a driver to a previously installed version if unidrv.dll errors began after updating a particular hardware device's driver.

10. Repair your installation of Windows. If the individual unidrv.dll file troubleshooting advice above is unsuccessful, performing a startup repair or repair installation should restore all Windows DLL files to their working versions.

11. Use a free registry cleaner to repair unidrv.dll related issues in the registry. A free registry cleaner program may be able to help by removing invalid unidrv.dll registry entries that might be causing the DLL error.
    

    We rarely recommend the use of registry cleaners. They're included as an option here as a "last resort" attempt before the destructive step coming up next.

12. Perform a clean installation of Windows. This will erase everything from the hard drive and install a fresh copy of Windows. If none of the steps above correct the unidrv.dll error, this should be your next course of action.

    All the information on your hard drive will be erased during this step. Make sure you've made the best attempt possible to fix the unidrv.dll error using a troubleshooting step prior to this one.

13. Troubleshoot for a hardware problem if any unidrv.dll errors persist. After a clean Windows installation, your DLL problem can only be hardware related.

Need More Help?

If you're not interested in fixing this problem yourself, see How Do I Get My Computer Fixed? for a full list of your support options, plus help with everything along the way like figuring out repair costs, getting your files off, choosing a repair service, and a lot more.