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I have the error: The program can´t start because nspr4.dll is missing. If I uninstall firefox the error is solved

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  • Last reply by cor-el

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Hi,

My boss has the error: The program can´t start because nspr4.dll is missing. When he uninstall the Firefox (last version) the error is solved. Please, how can I help him to use the firefox without appear this error when the windows starts?

Thank you very much, Ana Cristina

Hi, My boss has the error: The program can´t start because nspr4.dll is missing. When he uninstall the Firefox (last version) the error is solved. Please, how can I help him to use the firefox without appear this error when the windows starts? Thank you very much, Ana Cristina

All Replies (2)

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Hello,

Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove Firefox program files and then reinstall Firefox. Please follow these steps:

Note: You might want to print these steps or view them in another browser.

  1. Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer.
  2. After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu).
  3. Delete the Firefox installation folder, which is located in one of these locations, by default:
    • Windows:
      • C:\Program Files\Mozilla Firefox
      • C:\Program Files (x86)\Mozilla Firefox
    • Mac: Delete Firefox from the Applications folder.
    • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory. YOUR PROFILE FOLDER IS LOCATED ELSEWHERE.
  4. Now, go ahead and reinstall Firefox:
    1. Double-click the downloaded installation file and go through the steps of the installation wizard.
    2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

Please report back to see if this helped you!

Thank you.

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If you keep having problems then try to disable your security (anti-virus) software temporarily.