How to Fix Zlib1.dll Not Found or Missing Errors

Screenshot of a zlib1.dll error message in Windows

Tim Fisher 

The zlib1.dll file is related to the zlib compression library. Zlib1.dll errors are caused by situations that lead to the removal or corruption of the zlib1 DLL file

In some cases, zlib1.dll errors could indicate a registry problem, a virus or malware issue, or even a hardware failure.

There are several different ways that zlib1.dll errors can show up on your computer. Here are some of the more common ways that you might see zlib1.dll errors:

Zlib1.dll Not Found
This application failed to start because zlib1.dll was not found. Re-installing the application may fix this problem.
Cannot find [PATH]\zlib1.dll
The file zlib1.dll is missing.
Cannot start [APPLICATION]. A required component is missing: zlib1.dll. Please install [APPLICATION] again.

Zlib1.dll error messages might appear while using or installing certain programs, when Windows starts or shuts down, or maybe even during a Windows installation.

The context of the zlib1.dll error is an important piece of information that will be helpful while solving the problem.

The zlib1.dll error message could apply to any program or system that might utilize the file on any of Microsoft's operating systems including Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, and Windows 2000.

How to Fix Zlib1.dll Errors

Do not download zlib1.dll from a "DLL download" website. There are many reasons why downloading a DLL file is a bad idea. If you need a copy of zlib1.dll, it's best to obtain it from its original, legitimate source.

Start Windows in Safe Mode to complete any of the following steps if you're unable to access Windows normally due to the zlib1.dll error.

  1. Restore zlib1.dll from the Recycle Bin. The easiest possible cause of a "missing" zlib1.dll file is that you've mistakenly deleted it.

    Recovering a deleted copy of zlib1.dll with a file recovery program is a smart idea only if you're confident you've deleted the file yourself and that it was working properly before you did that.


  2. Run a virus/malware scan of your entire system
    . Some zlib1.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 zlib1.dll error you're seeing is related to a hostile program that's masquerading as the file.

  3. Reinstall the program that uses the zlib1.dll file. If the zlib1.dll DLL error occurs when you use a particular program, reinstalling the program should replace the file.

    Try your best to complete this step. Reinstalling the program that provides the zlib1.dll file, if possible, is a likely solution to this DLL error.


  4. Install MinGW and copy the zlib1.dll file to where you need it
    . Follow this step if you're not having luck getting the zlib1.dll file from reinstalling the program that uses it.


  5. Use System Restore to undo recent system changes
    . If you suspect that the zlib1.dll error was caused by a change made to an important file or configuration, a System Restore could solve the problem.

  6. Update the drivers for hardware devices that might be related to zlib1.dll. If, for example, you're receiving a "The file zlib1.dll is missing" error when you play a 3D video game, try updating the drivers for your video card.

    The zlib1.dll file may or may not be related to video cards or multimedia programs — this was just an example. The key here is to pay very close attention to the context of the error and troubleshoot accordingly.

  7. Roll back a driver to a previously installed version if zlib1.dll errors began after updating a particular hardware device's driver.

  8. 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 zlib1.dll errors as they fail.

  9. Repair your installation of Windows. If the individual zlib1.dll file troubleshooting advice above is unsuccessful, performing a startup repair or repair installation should restore all Windows DLL files to their working versions.

  10. Use a free registry cleaner to repair zlib1.dll related issues in the registry. A free registry cleaner program may be able to help by removing invalid zlib1.dll registry entries that might be causing the DLL error.

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


  11. Perform a clean installation of Windows
    . A clean install of Windows will erase everything from the hard drive and install a fresh copy of Windows. If none of the steps above correct the zlib1.dll error, this should be your next course of action.

    • After this step, you'll likely need to repeat Step 4 to get the program that supplies the zlib1.dll file.

    All the information on your hard drive will be erased during a clean install. Make sure you've made the best attempt possible to fix the zlib1.dll error using a troubleshooting step prior to this one.

  12. Troubleshoot for a hardware problem if any zlib1.dll errors persist. After a clean install of Windows, your DLL problem can only be hardware related.

Need More Help?

If you're not interested in fixing this problem yourself, even with help, 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 whole lot more.