When trying to load Half Life "Opposing Force" I get the following error messages:Debug assertion failed
Program:..files\valve\steam\steamapps\gokeeffe\opp osingforce\hl.exe
File: dbgheap.c
line 1132
Expression:_CrtlsvalidHeapPointer(pUserData)
For information on how your program can cause an assertion failure, see the Visual C++ documentation on asserts-Press retry to debug tha application
There are several of these error messages, and some include the following:
"Damage:before(null)block#183524245)at0x08f353 58" and
"Damage:after(null)block#183524245)at 0x08f31cb0" as well the the other wording above. There is an option to 'retry, abort or ignore' none of which do anything except eventually close the program

I understand None of this. I tried to load the game from a partition backup containing it (the backup is only 2 days old) and that resulted in the same error. I don't get the error with any other video files or games I open.

I recently reinsstalled the OS (XP-SP2) and have all updates installed. I also uninstalled the game, forgot I wanted part of it to finish, and reinstalled the game and that's when the errors started. I consider myself an intermediate user but this is beyond me. I have a Dell 8400, Intel P4, 560, 3.6 GHz w/HT, 1GB DDR2 SDRAM@400MHz, Radeon X700PRO, 160 GB HD

Hi Gokeefe,

Welcome to PCHF!

We have a great staff of tech experts who will be glad to help you get to the bottom of this.

Did you say you uninstalled the game partially and re-installed?

I'm not quite following you here.

I really don't get the whole clue of your story. You uninstalled the whole game but you missed a part :S Fully delete the whole game and then install again. The error says that a part of the hl.exe code is corrupt, so you'll have to reinstall it.