Crash signature - RtlpCoalesceFreeBlocks or RtlAllocateHeap

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Crash signatures ( what's this? ): RtlpCoalesceFreeBlocks and RtlAllocateHeap

Crashes in RtlpCoalesceFreeBlocks and RtlAllocateHeap can have several causes, mostly involving third-party software such as plugins or monitoring software.


Firefox crashes when you open it

AVG SafeSearch is the most common culprit for this crash signature if Firefox crashes as soon as you try to open it

Update AVG

Older versions of AVG Safe Search are particularly prone to this crash.

  1. Download the latest version of AVG Free or AVG Full edition.
  2. Restart your computer
  3. Run the installer you just downloaded -- it will overwrite the existing AVG install.

Make sure you are not running a program that conflicts with AVG

The following programs are known to conflict with AVG and may cause it to crash, crashing Firefox as well. This list is taken from the AVG Free FAQ

  • Webroot Spysweeper
  • Session Manager 0.6.1.13 add-on
  • Dell Network Assistant
  • Logitech QuickCam drivers

If you can open Firefox in Safe Mode, you may be able to disable AVG extensions such as AVG Safe Search.

At the top of the Firefox windowOn the menu bar, click the Help menuFirefox button, go over to the Help menu and select Restart with Add-ons Disabled.... Firefox will start up with the Firefox Safe Mode dialog.
For Windows XP, click the Help menu and select Restart with Add-ons Disabled.... Firefox will start up with the Firefox Safe Mode dialog.
Note: You can also start Firefox in Safe Mode by holding down the shift key while starting Firefox.holding down the option key while starting Firefox.quitting Firefox and then going to your Terminal and running: firefox -safe-mode
You may need to specify the Firefox installation path (e.g. /usr/lib/firefox-4)
At the top of the Firefox window, click on the Firefox button (File menu in Windows XP) and then click ExitOn the menu bar, click on the Firefox menu and select Quit FirefoxAt the top of the Firefox window, click on the File menu and select QuitAt the top of the Firefox window, click on the File menu and select ExitOn the menu bar, click on the Firefox menu and select Quit FirefoxAt the top of the Firefox window, click on the File menu and select Quit. Then in Windows, click Start, open the All Programs list and navigate to the Mozilla Firefox folder. In the Mozilla Firefox folder, select Mozilla Firefox (Safe Mode).Then hold down the option key as you restart Firefox.Go to your Terminal and run: firefox -safe-mode
You may need to specify the Firefox installation path (e.g. /usr/lib/firefox-3.5). Firefox will start up with the Firefox Safe Mode dialog.
Note: You can also start Firefox in Safe Mode by clicking Start, selecting Run (or use the Start Search box in Windows 7 and Vista) and then entering the following in the text field: firefox -safe-mode

  1. Select Continue In Safe Mode.
  2. From the Tools menu select Add-ons.
  3. Select the Extensions panel.
  4. Select AVG Safe Search and click Disable.
  5. Click on Restart Firefox.


Other crashes with this signature

Other causes of this crash can include Speedbit download accelerator, Venturi Firewall, QuickTime plugin. If you use these programs, updating them may help.

Contributors to this page: Chris_Ilias