What to do when Userdata.dll is missing in Windows 10

Matthew Adams
by Matthew Adams
Windows & Software Expert
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  • Userdata.dll issues are usually generated by some corrupted registry files or even outdated drivers.
  • Fixing the problem is something that even non-techies can do, so here a simple guide.
  • Learn how to get the best of your OS using the material in our Windows 10 section.
  • Find more easy-to-follow tutorials in our Troubleshooting Hub.
What to do when Userdata.dll is missing in Windows 10

Userdata is a shared DLL (Dynamic Link Library) system file that some software need to run.

Some users have stated that a userdata.dll error message pops up whenever they start Windows or when trying to manually open a specific program.

The userdata.dll error message states: This application failed to start because userdata.dll was not found. Reinstalling the application may fix this problem.

This error message usually pops up when the userdata.dll is either missing or corrupted in some way. Consequently, software that need the userdata file can’t access it.

The same error message can pop up for other DLL files, and the fixes for it are pretty similar. Keep reading to learn how to fix the userdata.dll is missing error message in Windows 10.

How can I solve userdata.dll problems in Windows 10?

  1. Update device drivers
  2. Run a System File Checker scan
  3. Scan the Registry with CCleaner
  4. Remove programs from the Windows Startup
  5. Roll back Windows with System Restore
  6. Reinstall the software
  7. Get a new userdata.dll file
  8. Add DLL Fixer software to Windows

1. Update device drivers

Some users have stated that updating hardware drivers fixed the userdata.dll is missing error. So updating outdated or corrupted drivers is a potential resolution for the userdata.dll error.

However, it’s hard to tell what drivers you’ll need to update. Your best bet is to add software to Windows 10 that will scan your drivers.

DriverFix is a tool that you can update AMD, Nvidia and Intel drivers with, among others.

DriverFix automatically update drivers

You can download the tool for free to your Windows device by visiting the website indicated below.

Upon launch, the software automatically scans drivers and lists any that need updating.

Select each indicated driver in turn and click the Update button to get the latest version compatible with your system.



Corrupt or outdated .dll files can cause a lot of trouble, but keeping your drivers up-to-date eliminates a lot of potential problems.
Free trial Visit website

2. Run a System File Checker scan

  1. Enter command prompt in the home screen search box.
  2. Right-click Command Prompt and select Run as administrator to open its window.
  3. Next, write the following command and press Enter: DISM.exe /Online /Cleanup-image /Restorehealth
  4. Then input sfc /scannow in the Prompt, and press the Enter key.
  5. Restart Windows if Windows Resource Protection does repair corrupted files.

Run a third-party DLL fixer

There are plenty of third-party programs out there that promise to fix or replace missing or broken DLLs, and most of them stay true to their word. However, if you are to choose just one, then there’s no way you can go wrong with Restoro.

How to use Restoro to fix missing or broken DLLs

  1. Download here Restoro and install it on your Windows 10 PC
  2. Let Restoro perform a full system scan
  3. When the scan is finished, press Clean Now
    • This is when you will have to activate your license key
    • Before the repair process starts, Restoro will create a restore point of your system in case things go wrong
  4. Restoro will now proceed to fix your DLL-related issue.

Note: While Restoro can be downloaded for free, it has limited functionality until you activate it. That being the case, if you want the full benefit of a great PC repair and optimization tool, you should purchase the full license.

3. Scan the Registry With CCleaner

  1. Download CCleaner for free and wait for the setup to finish.
  2. Open CCleaner and click Registry on the left of CCleaner’s window to open the registry cleaner.Clean registry errors
  3. Select all the registry check boxes, and press the Scan for Issues button.
  4. Click the Fix selected Issues button.
  5. Next, select the Yes option if you prefer to save a backup file (although you probably won’t need it).
  6. Press the Fix All Selected Issues button to repair the registry.


With this simple and intuitive tool, anyone can efficiently repair registry errors.

4. Remove programs from the Windows Startup

  1. Pree Win + X and select Task Manager from the menu.fix audio buzzing
  2. Click the Start-up tab.
  3. Then you can remove programs from the Windows startup by selecting them and clicking Disable.

Some users have said that they fixed the issue by removing the Password Manager Pro and Fingerprint Reader programs.

Thus, it might be the case that a startup program generates the error message. So removing software from the system startup is another potential fix for the userdata.dll error.

5. Roll back Windows with System Restore

System Restore can come in handy for fixing corrupted DLL files. With this utility, you can restore Windows 10 to an earlier point in time, which can fix corrupted system files.

in this case, you should select a restore point that will restore Windows to a date when the DLL error message did not pop up on your laptop or desktop.

This is how you can roll back Windows:

  1. Right-click the Start menu and select Run.
  2. Enter rstrui in Run’s Open text box and click OK to open the System Restore window.
  3. Click the Choose a different restore point option as an alternative to the recommended restore.
  4. Press the Next button to open the list of restore points.
  5. To view the full restore list, click the Show more restore points option.
  6. Choose a restore point to roll Windows back to.
  7. Restoring Windows removes programs installed after a selected restore point.
  8. You can press the Scan for affected programs button to see what software is deleted for a specific restore point.
  9. Click Next and Finish to roll back Windows.

6. Reinstall the software

  1. Open Run as shown before.
  2. Input appwiz.cpl in the box and click OK.
  3. This will open Control Panel, where you have to select the program that returns the DLL error message, and click the Uninstall button.
  4. Click the Yes button to confirm.
  5. Restart Windows after uninstalling the program.
  6. Then reinstall the latest version of the software. You can usually download the latest version from the software’s website.

Note that the userdata.dll is missing error message states, Reinstalling the application may fix this problem. So that’s one hint about the specific app which might cause the error. 

7. Get a new userdata.dll file

  1. Open the official DLL files webpage in your browser.
  2. Click Download to save the userdata.dll ZIP.
  3. Open the userdata ZIP in File Explorer.
  4. Press the Extract all button.
  5. Click Browse to select a folder path to extract the ZIP to, and click the Extract button.
  6. Open the extracted userdata.dll folder in File Explorer.
  7. Select the userdata.dll file, and press the Copy to button.
  8. Select to copy it to the System32 folder.
  9. Then select the original userdata.dll file in the folder you exacted it to, and press the Delete button.
  10. Restart your desktop or laptop.
  11. You might also need to register the DLL file. To do so, press the Windows key + X hotkey and select Command Prompt (Admin).
  12. Enter regsvr32 userdata.dll in the Command Prompt’s window, and press Enter.
  13. Click Restart on the Start menu.

8. Add DLL Fixer software to Windows

add DLL Fixer software to Windows

There are numerous DLL fixer software for Windows that fix DLL errors. DLL Suite, DLL Tool, DLL Files Fixer, and Free DLL Fixer are some of the utilities that scan for and repair corrupted DLL files.

They also include databases that you can get replacement DLL files from. As such, those utilities might come in handy for fixing the userdata.dll is missing error. You can try out an unregistered version of DLL Suite by clicking the Start Download button on this page.

So these are a few resolutions that should fix the userdata.dll is missing error in Windows 10.

Note that some of the above resolutions might also fix missing DLL error messages for other files.

Editor’s Note: This post was originally published in October 2018 and was revamped and updated in October 2020 for freshness, accuracy, and comprehensiveness.

Editor's Note: This article was originally published in October 2018 and was revamped and updated in November 2020 for freshness, accuracy, and comprehensiveness.
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