I've just recently tried to start up MTA and received this message
Version = 1.0.4-release-2033.2.015
Time = Sun Nov 28 20:14:00 2010
Module = c:\program files\steam\steamapps\common\grand theft auto san andreas\gta_sa.exe
Code = 0xC0000005
Offset = 0x00346929
EAX=00000000 EBX=00000000 ECX=0000002D EDX=0000002C ESI=00000000
EDI=767C92A5 EBP=0022FF88 ESP=0022FDD8 EIP=00746929 FLG=00010246
CS=001B DS=0023 SS=0023 ES=0023 FS=003B GS=0000
Also I use SA:MP which also stopped working