sorry i forgot to mention that when i download .exe files it freezes at 1 second remaining.

here's a screenshot

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

You can set the browser.download.manager.scanWhenDone pref to false on the about:config page.

thanks for the reply, but i don't have an anti-virus

You can still try to set the above mentioned pref browser.download.manager.scanWhenDone to false.

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

Thanks for the help, i tried turning browser.download.manager.scanWhenDone to false but it didn't work, and i tried to boot windows in Windows Safe Mode with network support, but when i do it "the blue screen of death comes", i don't know why but some file like winrar and msxml.exe were downloaded but when i try to download files like U-torrent and adobe flash player it stops at some second remaining

Hi gamedeveloper0,

Thank you for contacting support. Blue screens of death haunt my dreams. If there was an error message on the blue screen of death then you can look up the error reference in Microsoft's forum, hopefully it is not a hardware issue!

In our knowledge base there is more troubleshooting, have you already tried reseting the download actions? http://mzl.la/LJ0h2w

• Reset download actions for all file types
• Reset the download folder

Do a malware check with some 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: Home Page:
  http://www.microsoft.com/windows/products/winfamily/defender/default.mspx
• 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

You could had prevented this if you kept your windows XP system (soon to be unsupported no matter what April 2013) updated to SP3 instead of SP2.

• http://support.microsoft.com/kb/322389

AND

• http://support.microsoft.com/kb/306525