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Why does Firefox warm me that pdf is an executable file?

  • 1 reply
  • 2 have this problem
  • 55 views
  • Last reply by Tonnes

mistertdba
mistertdba
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Hello, I am using Firefox Quantum 57.0 (64-bit) on macOSSierra version 10.12.6. I have noticed that Firefox warns me when I download pdf files. The message says:

"“Measures_&_Metrics_Mini_1-15-08_Update_102811.pdf” is an executable file. Executable files may contain viruses or other malicious code that could harm your computer. Use caution when opening this file. Are you sure you want to launch “Measures_&_Metrics_Mini_1-15-08_Update_102811.pdf”?"

The pdf file is genuine pdf file and not an executable. I have noticed that the warning message is displayed for all pdf files in the download button of Firefox tool bar.

Thank you for your support in advance.

Hello, I am using Firefox Quantum 57.0 (64-bit) on macOSSierra version 10.12.6. I have noticed that Firefox warns me when I download pdf files. The message says: "“Measures_&_Metrics_Mini_1-15-08_Update_102811.pdf” is an executable file. Executable files may contain viruses or other malicious code that could harm your computer. Use caution when opening this file. Are you sure you want to launch “Measures_&_Metrics_Mini_1-15-08_Update_102811.pdf”?" The pdf file is genuine pdf file and not an executable. I have noticed that the warning message is displayed for all pdf files in the download button of Firefox tool bar. Thank you for your support in advance.

Chosen solution

Perhaps the handler settings for PDF files are incorrect, or even damaged.

Please have a look at the View PDF files using Firefox’s built-in viewer as well as the Manage file types and download actions in Firefox support article and let us know if you need additional help. You might just need to change a setting or remove the handlers.json file in your profile folder.

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Tonnes
Tonnes
  • Locale Leader
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Chosen Solution

Perhaps the handler settings for PDF files are incorrect, or even damaged.

Please have a look at the View PDF files using Firefox’s built-in viewer as well as the Manage file types and download actions in Firefox support article and let us know if you need additional help. You might just need to change a setting or remove the handlers.json file in your profile folder.