Create a new profile as a test to check if your current profile is causing the problems.

See "Basic Troubleshooting: Make a new profile":

• https://support.mozilla.org/kb/Basic+Troubleshooting#w_8-make-a-new-profile

There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.

If that new profile works then you can transfer some files from the old profile to that new profile, but be careful not to copy corrupted files.

See:

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

See:

• http://kb.mozillazine.org/Firefox_crashes
• https://support.mozilla.org/kb/Firefox+crashes
• https://support.mozilla.org/en-US/kb/latest-firefox-issues

If you have submitted Breakpad crash reports then post the IDs of one or more Breakpad crash reports (bp-xxxxxxxx-xxxxxxxxx-xxxx-xxxxxxxxxxxx). You can find the IDs of the submitted crash reports on the about:crashes page. You can open the about:crashes page via the location bar, like you open a website.

See:

• http://kb.mozillazine.org/Breakpad (Mozilla Crash Reporter)
• https://support.mozilla.org/kb/Mozilla+Crash+Reporter
• https://developer.mozilla.org/en/How_to_get_a_stacktrace_for_a_bug_report

The "Tell websites I do not want to be tracked" setting doesn't have anything to do with cookies.
It only makes Firefox send a DNT=1 header as part of the response headers that are send to the server.

You can also do a malware check with some malware scanning programs on the Windows computer.
You need to scan with all programs because each program detects different malware.
Make sure that you update each program to get the latest version of their databases before doing a scan.

• http://www.malwarebytes.org/mbam.php - Malwarebytes' Anti-Malware
• http://www.superantispyware.com/ - SuperAntispyware
• http://www.microsoft.com/security/scanner/en-us/default.aspx - Microsoft Safety Scanner
• http://www.microsoft.com/windows/products/winfamily/defender/default.mspx - Windows Defender: Home Page
• http://www.safer-networking.org/en/index.html - Spybot Search & Destroy

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

• http://support.kaspersky.com/viruses/solutions?qid=208280684

See also:

• "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked

@cor-el thank you for answer. i have been scanned the system by several scanning programs and they don't detected anything.

@Swarnava I removed all report before in about:crashes (had so many crashes). By few minutes ago firefox has agiane to crash and i submit report. Now I worked with disabeled all Plagins (last crashe with enabeled firebug).

Thank you for reply

UPD: Creating a new profile can't solve this issue.

If a new profile didn't fix it then it is more likely caused by other (security) software on your computer.

Can you post the cash IDs of some recent crash reports and verify that the crashes do have a not empty crash signature (@ EMPTY) by opening the links?

@cor-el You are right. Today Mozilla Thunderbird crashed too. Thank you for your reply.