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why did firefox change my .PDF files to .html

  • 4 replies
  • 6 have this problem
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  • Last reply by geneb53

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I am running windows XP home edition service pack 3, a 32 bit version. I have pcmatic for an anti virus program and it did not like my version of adobe reader( it kept trying to update it to a newer version that doesn't support windows XP. ( it took forever to run a scan, because it downloaded an update that it couldn't install). So I deleted adobe reader and had no more grief from the scans...But...I had .pdf files in my download folder on my desktop and found that they were changed to firefox .HTML extensions.. when I try to open these html files, I get a blank Firefox page and a popup that asks me to download or open the file. whether I select open or download it just keeps opening another tab asking the same thing:::I'm requesting your help to fix this problem.. I think I might have shot myself in the foot by deleting adobe reader instead of trying to put it on a local whitelist. Will have to figure out how to do that and if it would cause pcmatic to skip over my version of adobe reader.. thanking you in advance geneb53 P.S. I am on a different computer than the one giving me the problem..it's my first time here and I didn't know.

I am running windows XP home edition service pack 3, a 32 bit version. I have pcmatic for an anti virus program and it did not like my version of adobe reader( it kept trying to update it to a newer version that doesn't support windows XP. ( it took forever to run a scan, because it downloaded an update that it couldn't install). So I deleted adobe reader and had no more grief from the scans...But...I had .pdf files in my download folder on my desktop and found that they were changed to firefox .HTML extensions.. when I try to open these html files, I get a blank Firefox page and a popup that asks me to download or open the file. whether I select open or download it just keeps opening another tab asking the same thing:::I'm requesting your help to fix this problem.. I think I might have shot myself in the foot by deleting adobe reader instead of trying to put it on a local whitelist. Will have to figure out how to do that and if it would cause pcmatic to skip over my version of adobe reader.. thanking you in advance geneb53 P.S. I am on a different computer than the one giving me the problem..it's my first time here and I didn't know.

Chosen solution

Hello Steven Fox, I thank you for your idea to re-enable Firefox to open PDF files. I went to the link provided and followed the instructions very carefully...BUT, that link was for Firefox 15 and the files in the (about:config) were not the same as in my version of Firefox 44.. HOWEVER ;

  I did have success by refreshing my Firefox browser and turning off hardware acceleration.     My PDF files now open in Firefox PDF reader and display correctly.
  Again many thanks for your efforts on my behalf, and I hope other members find this useful .. geneb53
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I really hate security applications that force updates to installed applications as PC Matic did for you. I would ask their support how to diasble that "nanny" feature when they can't "do it right".

Overall, it sounds like corruption in the Windows Registry with regards to the PDF file format strings. And IMO it might be easier to just re-install Windows than to figure out what's wrong and then set about to fix it.

My advice is to install a different PDF application like Free Foxit PDF Reader (on the left side of that page), which I used in past years, before Firefox got its own PDF reader. And 'hope' a different PDF application fixes what got broken.

Of course the ultimate "fix" is to run an operating system that is still supported and not in End-of-Life status which most software barely supports any longer, if they still support it at all. I switched from WinXP to Win7 nine months ago due to issues similar to yours - lack of 'good' support for mainstream applications that interfaced with Firefox.

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Hello Mr Ed-Meister, I thank you for the rapid reply, I believe like you that the registry has a problem. But like an automatic transmission in a car, the registry is just one place I don't care to tread. I noticed that you replaced XP with Windows 7, I was wondering if it affected your system speed? Did it slow the old XP system and hardware down or did it remain the same?..The wonderment is still how did the type of file extension change from .PDF to Firefox HTML . I will continue the fight to get this sorted and will advise you of any success. Regards GeneB53

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There are very easy instructions to follow here, on how to re-enable Firefox to open PDF files:

http://www.howtogeek.com/123617/how-to-enable-firefoxs-built-in-pdf-reader/

I would not go the Windows 7 route on that machine; by the time you upgrade Windows 7 and its seven years' worth of updates, your computer would be slow as a snail. Or you could buy a new machine. I'm a diehard fan of XP and would not go through all that just to read PDF files.

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Chosen Solution

Hello Steven Fox, I thank you for your idea to re-enable Firefox to open PDF files. I went to the link provided and followed the instructions very carefully...BUT, that link was for Firefox 15 and the files in the (about:config) were not the same as in my version of Firefox 44.. HOWEVER ;

  I did have success by refreshing my Firefox browser and turning off hardware acceleration.     My PDF files now open in Firefox PDF reader and display correctly.
  Again many thanks for your efforts on my behalf, and I hope other members find this useful .. geneb53