Update your Flash Player Version 18.0.0.160
https://www.adobe.com/products/flashplayer/distribution3.html

See if there are updates for your graphics drivers https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

http://kb.mozillazine.org/Unable_to_save_or_download_files

http://kb.mozillazine.org/Issues_with_Firefox#Downloading_opening_or_saving_files

Hello, see also if the next helps : https://support.mozilla.org/en-US/questions/1026743#answer-644501

thank you

FredMcD said

Update your Flash Player Version 18.0.0.160
https://www.adobe.com/products/flashplayer/distribution3.html

When I click to download the installer, I get the same ""C:\Users\[user]\AppData\Local\Temp\.. source file could not be read." error

ideato said

Hello, see also if the next helps : https://support.mozilla.org/en-US/questions/1026743#answer-644501 thank you

I already tried that and it didn't work

Did you check out the other links I posted?

You can always use Windows Internet Explorer..(Ugg)

Also note; for flash, there is one installer for Windows, and another for others. install both.

What security software (firewall, anti-virus) do you have?

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:

• http://kb.mozillazine.org/Unable_to_save_or_download_files

jk11 said

ideato said

Hello, see also if the next helps : https://support.mozilla.org/en-US/questions/1026743#answer-644501 thank you

I already tried that and it didn't work

yes, I tried those other links. Windows update also isnt working

cor-el said

What security software (firewall, anti-virus) do you have? 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:

• http://kb.mozillazine.org/Unable_to_save_or_download_files

I think there is an issue with the antivirus. I had avira, panda and avast. When I installed AVG, I got problems with it and panda, so I uninstalled them, leaving just avira and avast

Even turning off the firewall isn't helping

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/

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.

• Malwarebytes' Anti-Malware:
  http://www.malwarebytes.org/mbam.php
• AdwCleaner:
  http://www.bleepingcomputer.com/download/adwcleaner/
  http://www.softpedia.com/get/Antivirus/Removal-Tools/AdwCleaner.shtml
• SuperAntispyware:
  http://www.superantispyware.com/
• Microsoft Safety Scanner:
  http://www.microsoft.com/security/scanner/en-us/default.aspx
• Windows Defender:
  http://windows.microsoft.com/en-us/windows/using-defender
• Spybot Search & Destroy:
  http://www.safer-networking.org/en/index.html
• Kasperky Free Security Scan:
  http://www.kaspersky.com/security-scan

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

• Anti-rootkit utility TDSSKiller:
  http://support.kaspersky.com/5350?el=88446

See also:

• "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked
• https://support.mozilla.org/kb/troubleshoot-firefox-issues-caused-malware

by disabling avira and its firewall, I was able to download the adobe flash player. But that still didn't solve the problem

I'll try rebooting in safe mode now

in safe mode, I was able to download the pdf file I couldn't before. However, I am unable to even install Spybot, as I got the same source file is corrupted error. I also cannot open windows update

I was able to install AdwCleaner, and it deleted some stuff. However, I still can't open certain pdf files in non-safe mode

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.

I can't even install or run new antivirus programs. I was able to download UnThreat, but it won't run. I can't download Spybot even in safe mode

Are you using

Start your Computer in safe mode with networking. Then start Firefox. Try Safe web sites. Is the problem still there?

Starting The Computer In Safe Mode;
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