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Cannot Open PDF files in Firefox - Finally a Solution

  • 6 replies
  • 3 have this problem
  • 7 views
  • Last reply by FredMcD

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This is actually a solution to a PDF Problem - Read On.

Had a situation where I experienced Firefox was not able to open, or download for that matter, an email from a specific client, that contained a PDF attachment. I narrowed the problem down, after trying all of the recommended solutions, to the file name containing the string '_%_' within it's name.

Turns out this is the problem. Whatever program that the user was using to create the email with the attachment, included this string in the actual File Name of the attachment. I could use IE to at least save the file, which is what led me to the solution, by allowing me to see the string in the file name. I had already tried Safe Mode, About:Config changes on pdfjs.disabled, as well as all of the other solutions about not being able to open a PDF file within Firefox. However, I found no solution that included this one little tid-bit of information.

To confirm my solution, I loaded my webmail client in IE and Firefox, logged in as the same user, then used a known good PDF file, that I made a copy of. Then via two emails with IE, I sent one email to self with the copy, and one email to self with the copy that I renamed to include the '_%_' string: Example

File name in first email: A File Named Bob.pdf File name in Second Email: A File Named Bob_%_.pdf

Firefox handled the first email without a hitch. Second email, it did not know what to do with it...

Anyway, wanted to provide this solution, since it seems that no other person has run into this issue.

This is actually a solution to a PDF Problem - Read On. Had a situation where I experienced Firefox was not able to open, or download for that matter, an email from a specific client, that contained a PDF attachment. I narrowed the problem down, after trying all of the recommended solutions, to the file name containing the string '_%_' within it's name. Turns out this is the problem. Whatever program that the user was using to create the email with the attachment, included this string in the actual File Name of the attachment. I could use IE to at least save the file, which is what led me to the solution, by allowing me to see the string in the file name. I had already tried Safe Mode, About:Config changes on pdfjs.disabled, as well as all of the other solutions about not being able to open a PDF file within Firefox. However, I found no solution that included this one little tid-bit of information. To confirm my solution, I loaded my webmail client in IE and Firefox, logged in as the same user, then used a known good PDF file, that I made a copy of. Then via two emails with IE, I sent one email to self with the copy, and one email to self with the copy that I renamed to include the '_%_' string: Example File name in first email: A File Named Bob.pdf File name in Second Email: A File Named Bob_%_.pdf Firefox handled the first email without a hitch. Second email, it did not know what to do with it... Anyway, wanted to provide this solution, since it seems that no other person has run into this issue.

Chosen solution

Here is the solution:

Turns out this is the problem. Whatever program that the user was using to create the email with the attachment, included this string in the actual File Name of the attachment. I could use IE to at least save the file, which is what led me to the solution, by allowing me to see the string in the file name. I had already tried Safe Mode, About:Config changes on pdfjs.disabled, as well as all of the other solutions about not being able to open a PDF file within Firefox. However, I found no solution that included this one little tid-bit of information.

To confirm my solution, I loaded my webmail client in IE and Firefox, logged in as the same user, then used a known good PDF file, that I made a copy of. Then via two emails with IE, I sent one email to self with the copy, and one email to self with the copy that I renamed to include the '_%_' string: Example

File name in first email: A File Named Bob.pdf File name in Second Email: A File Named Bob_%_.pdf

Firefox handled the first email without a hitch. Second email, it did not know what to do with it...

Anyway, wanted to provide this solution, since it seems that no other person has run into this issue.

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All Replies (6)

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Hi Techguy9, that is an interesting situation. The % is used in URLs to encode characters, for example, %20 is a space. If there is %_ perhaps that confuses Firefox. It seems like something the browser should be able to work around, so maybe file a bug? https://bugzilla.mozilla.org/

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Thanks. Will submit to Bugzilla

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That was very good work. Well done. Please flag your last post as Solved Problem so others will know.

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Looks like this has been solved...

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Chosen Solution

Here is the solution:

Turns out this is the problem. Whatever program that the user was using to create the email with the attachment, included this string in the actual File Name of the attachment. I could use IE to at least save the file, which is what led me to the solution, by allowing me to see the string in the file name. I had already tried Safe Mode, About:Config changes on pdfjs.disabled, as well as all of the other solutions about not being able to open a PDF file within Firefox. However, I found no solution that included this one little tid-bit of information.

To confirm my solution, I loaded my webmail client in IE and Firefox, logged in as the same user, then used a known good PDF file, that I made a copy of. Then via two emails with IE, I sent one email to self with the copy, and one email to self with the copy that I renamed to include the '_%_' string: Example

File name in first email: A File Named Bob.pdf File name in Second Email: A File Named Bob_%_.pdf

Firefox handled the first email without a hitch. Second email, it did not know what to do with it...

Anyway, wanted to provide this solution, since it seems that no other person has run into this issue.

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Well Done.