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Firefox 87 suddenly won't start. Error Msg: The code execution cannot proceed because VCRUNTIME140_1.dll was not found.

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  • 1 has this problem
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  • Last reply by RacerRon

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How do I fix this? Firefox won't start (it did a few days ago).

Version 87 running on Windows 10.

Error Msg: The code execution cannot proceed because VCRUNTIME140_1.dll was not found.

There is a file: VCRUNTIME140.dll in the C:\Program Files\Mozilla Firefox folder.

I reinstalled Firefox but that didn't help.

How do I fix this? Firefox won't start (it did a few days ago). Version 87 running on Windows 10. Error Msg: The code execution cannot proceed because VCRUNTIME140_1.dll was not found. There is a file: VCRUNTIME140.dll in the C:\Program Files\Mozilla Firefox folder. I reinstalled Firefox but that didn't help.

Chosen solution

  1. Enter this link: https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads
  2. From the section Visual Studio 2015, 2017 and 2019 download the following executable file: vc_redist.x64.exe
  3. Install this file
  4. Restart the computer and run Firefox
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Chosen Solution

  1. Enter this link: https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads
  2. From the section Visual Studio 2015, 2017 and 2019 download the following executable file: vc_redist.x64.exe
  3. Install this file
  4. Restart the computer and run Firefox
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Hi TyDraniu,

Your help worked like a charm. It's great to see experienced folks like you spend time and effort to help those of us who get in a jam and don't know what to do. I'm new to Windows 10 and working on setting up my new laptop like the Win 7 machine I've been using for 9 years.

After some thought, I'm guessing the VCRUNTIME140_1.dll file that was missing got removed when I uninstalled Windows 365, so I can install an older version of Word & Excel that I have.

In any case, I appreciate that you came to the rescue so fast. Very happy!

Thank you!