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Firefox gives a can't read source file message when downloading

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I have tried to download and install the Opera browser and other .exe files (because Firefox is not working correctly, as witnessed by this message). First, I have to pause and restart the downloads many times; second, after the download is apparently complete, I get the "source file could not be read". I don't know whether it is related, but pages rarely complete opening and require that I stop the loading process.

I clicked to add troubleshooting information and couldn't do it. Connection failure with Mozilla.

?????

I have tried to download and install the Opera browser and other .exe files (because Firefox is not working correctly, as witnessed by this message). First, I have to pause and restart the downloads many times; second, after the download is apparently complete, I get the "source file could not be read". I don't know whether it is related, but pages rarely complete opening and require that I stop the loading process. I clicked to add troubleshooting information and couldn't do it. Connection failure with Mozilla. ?????

All Replies (4)

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Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.


Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

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It is possible that anti-virus software is corrupting downloaded files or is interfering otherwise.

Try to disable the real-time (live) scanning of files in your anti-virus software temporarily to see if that makes downloading work.

See:

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Hardware Acceleration option is not where Fred McD says it is (I am using version 24 on purpose). I did find it, however, and turning it off did not solve the problem. Another person suggested changing the http:keepactive timeout from 115 to 0. This helped, but not when a website (particularly news sites) has many images. As I am writing this, the NY Times site keeps spinning. Stopping and refreshing doesn't do it. In addition, I can't upload pictures from the hard drive to Costco's photo site. Nor can I download the Opera browser, which I wanted to test on this issue. I am starting to suspect a corrupted file in the OS.

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Did you check your security software?

Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.


Do a malware check with several malware scanning programs on the Windows computer. Please scan with all programs because each program detects different malware. All these programs have free versions.

Make sure that you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also: