How to Fix Atl.dll Not Found or Missing Errors

Atl.dll errors are caused by situations that lead to the removal or corruption of the atl DLL file. In some cases, atl.dll errors could indicate a registry problem, a virus or malware issue, or even a hardware failure.

Microsoft calls this file the ATL Module for Windows XP (Unicode).

Atl.dll Errors

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

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

Because atl.dll should exist in the System32 folder, you might see an error when doing all sorts of things that require that important DLL file.

For example, the error message might be seen while using or installing certain programs like a web browser or the System Restore utility, when Windows starts or shuts down, or maybe even during a Windows installation.

How to Fix Atl.dll Errors

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

1. Restore atl.dll from the Recycle Bin. The easiest possible cause of a "missing" atl.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 atl.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 atl.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 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 atl.dll file. Since this DLL file is provided by Microsoft, the System File Checker tool should restore it.

5. Copy the atl.dll file from another location on your computer. Windows keeps a couple copies of this file, so if it's missing from C:\Windows\System32\ (which is where it should be), you should be able to find it elsewhere and put a copy in the System32 folder.

   In Windows 10 and other newer Windows versions, a subfolder within C:\Windows\WinSxS\ probably holds one copy. In Windows XP, and possibly older Windows versions, look for an atl.dll copy in C:\Windows\System32\dllcache\.

   You can search your whole computer with a program like Everything if you're having troubles using the built-in search tool in Windows.

   If you find atl.dll in one of those other secure locations, go ahead and copy it to the System32 folder. However, if you see atl.dll anywhere else, like on your desktop or in your downloads folder, promptly delete it since it's most likely not a genuine copy.

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

7. Update the drivers for hardware devices that might be related to atl.dll. If, for example, you're receiving a "The file atl.dll is missing" error when you play a 3D video game, try updating the drivers for your video card.

   The atl.dll file may or may not be related to video cards—this was just an example. The key here is to pay very close attention to the context of the error and troubleshoot accordingly.

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

9. 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 atl.dll file could be included in one of those updates.

10. Test your memory and then test your hard drive. We've left the majority of hardware troubleshooting to the last step, but your computer's memory and hard drive are easy to test and are the most likely components that might cause atl.dll errors as they fail.

    If the hardware fails any of your tests, replace the memory or replace the hard drive as soon as possible.

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

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

    We rarely recommend the use of registry cleaners (see why in our Registry Cleaners FAQ), but it's included here as a "last resort" attempt before the destructive step coming up next.

13. 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 atl.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 error using a troubleshooting step prior to this one.

14. Troubleshoot for a hardware problem if any atl.dll errors persist. After a clean install of Windows, your DLL problem can only be hardware related.