Msvcp100.dll errors happen when the msvcp100 DLL file is deleted or corrupted in some way. Sometimes, these errors can indicate a problem with the Windows registry, a virus or malware issue, or even a hardware failure.
This troubleshooting guide applies to any of Microsoft's operating systems, including Windows 11, Windows 10, Windows 8, etc., and might apply to any program that uses the DLL file directly or relies on it in some way.
Walk through these steps in order to see what works to fix your specific error. If Windows won't load because of problems with this DLL file, start Windows in Safe Mode first.
You should only download msvcp100.dll from a trusted, verified source that has a clean, unaltered copy of the DLL file. Never download it from a "DLL download" website-there are many reasons why downloading a DLL file like that is a bad idea.
Download the Microsoft Visual C++ 2010 Service Pack 1 Redistributable Package MFC Security Update and run it. This will replace/restore the msvcp100.dll with the most recent copy provided by Microsoft.
You're given more than one download option from Microsoft for this update, based on the version of Windows you have installed-x86 (32-bit) or x64 (64-bit). See How to Tell if You Have Windows 64-Bit or 32-Bit for help, if you're not sure what to choose.
Some users needed to install the redistributable for Visual Studio 2012, instead. If v2010 didn't work for you, reboot your computer to confirm that you still see the error, and then install v2012.
Install any available Windows updates. The standalone installation in the previous step should take care of this, but it's possible a service pack or patch installed by Windows Update may also replace or update the file that's causing the errors.
Restore msvcp100.dll from the Recycle Bin. A simple reason for a "missing" msvcp100.dll file is that you've accidentally deleted it.
If you think you may have inadvertently deleted this file, but it's not in the Recycle Bin, it's possible you've already emptied it. You can try to recover it with a free file recovery program.
You may have deleted msvcp100.dll because it wasn't working right or because it was infected with malicious computer code. Be sure the file you restore was working properly prior to deleting it before you attempt to recover it.
Run a virus/malware scan of your entire system. It's possible that your specific errors are caused by a virus or other malware infection that resulted in the DLL file become unusable.
Use System Restore to undo recent system changes. Using System Restore to revert important system files to a previous version should fix msvcp100.dll errors that are caused by changes to these types of system files.
Reinstall the program that's producing the error. If you see the error when you're first opening a particular program, or while you're using that software, then the error is most likely being caused by that application, in which case reinstalling it should help.
Every program that uses this DLL file is using the copy that's stored in one of these folders:
C:\Windows\System32\
C:\Windows\SysWOW64\
As long as those folders contain a clean copy of the file, then the program you reinstall should end up using the same file.
Repair your installation of Windows. If the individual msvcp100.dll file troubleshooting advice above isn't proving to be helpful in eliminating the DLL errors, performing a startup repair or repair installation should restore all Windows DLL files to their working versions.
Test your memory and then test your hard drive. Your computer's memory and hard drive are really easy to test for problems, and they might just be related to these errors.
If these hardware tests fail, even if they don't fix the msvcp100.dll problems, you should most likely replace the memory or replace the hard drive as soon as possible.
Use a free registry cleaner to repair any issues in the registry that might be caused by the msvcp100.dll file. This is usually accomplished by having the application delete invalid registry entries that might be causing the error.
We've included this option only as a last non-destructive attempt at fixing the DLL error before moving on to the next step-we rarely recommend the use of registry cleaners (see why in our Registry Cleaners FAQ).
Perform a clean installation of Windows to delete everything from the hard drive and install a new, hopefully, error-free copy of Windows with fresh DLL files. If none of the steps above correct the error, this should be your next course of action.
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 error using a troubleshooting step prior to this one.
You may need to repeat Step 1 after installing a fresh copy of Windows if the problem persists past this step.
Troubleshoot for a hardware problem if the software-related steps from above still haven't resolved the msvcp100.dll errors. After a clean install of Windows, the DLL problem can only be hardware related.
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.
Several error messages can indicate an issue with the msvcp100.dll file, like some of these more common ones:
Be careful not to mix this up with msvcp110.dll errors and others like it.
You might run into one of these error messages when Windows is first starting up or even when it's shutting down, while a particular program is being installed or used, or maybe even during a new Windows installation.
No matter when the error is shown, it's an important step in troubleshooting to identify that time-to see when exactly the msvcp100.dll error is happening. Knowing the context is a huge part of identifying how to fix the problem.