This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Denne tråden ble arkivert. Still et nytt spørsmål dersom du trenger hjelp.

cannot start Firefox because of Netapi32.dll error

  • 3 svar
  • 1 har dette problemet
  • 2 views
  • Siste svar av cor-el

kitzbuel
kitzbuel
more options

I am getting an error saying "c:\windows\system32\netapi32.dll is either not designed to run on Windows or it contains an error. Try installing the program again using the original installation media or contact your system administrator or the software vendor for support. Error status 0xc0000020."

When I close that error window I get another error saying "Couldn't load XPCOM".

I have uninstalled Firefox and deleted the Mozilla folders from all profiles and tried reinstalling it, but still get the error. I did a system restore to a checkpoint dated prior to when the problem began, but that did not resolve the issue either.

I am getting an error saying "c:\windows\system32\netapi32.dll is either not designed to run on Windows or it contains an error. Try installing the program again using the original installation media or contact your system administrator or the software vendor for support. Error status 0xc0000020." When I close that error window I get another error saying "Couldn't load XPCOM". I have uninstalled Firefox and deleted the Mozilla folders from all profiles and tried reinstalling it, but still get the error. I did a system restore to a checkpoint dated prior to when the problem began, but that did not resolve the issue either.

All Replies (3)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
more options

For the XPCOM, when you reinstalled, did you first rename this folder:

C:\Program Files (x86)\Mozilla Firefox\

If not, rename that to

C:\Program Files (x86)\OldFirefox\

and install again (no need to uninstall first). This can help resolve the issue of inconsistent/mixed version program files.

For the other error, if system file checker doesn't fit is, it may indicate a malware problem. For intensive malware support, you can use the forums listed in our malware support article.

kitzbuel
kitzbuel Eieren av spørsmålet
more options

I did that, the install recreated the Mozilla Firefox folder and then the "Couldn't load XPCOM" error popped up.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

This usually happens because of a failed Firefox update that left you with a mixture of old and updated files in the Firefox program folder.

Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.

If possible uninstall your current Firefox version to cleanup the Windows registry and settings in security software.

  • Do NOT remove "personal data" when you uninstall your current Firefox version, because this will remove all profile folders and you lose personal data like bookmarks and passwords including data in profiles created by other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

  • (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
  • (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure NOT to remove personal data when you uninstall Firefox as that will remove all Firefox profile folders and you lose your personal data.

You may have to disable your security software temporarily if the problem persists.