every time I open a pdf file shows this message:
error occurred in the application at location unknown software exception 0x00416ba6
Details: windows xp, adobe reader xi
There is a very good chance that you are seeing the effects of a hijackware infection!
NB: If you had no anti-virus application installed or the subscription had expired *when the machine first got infected* and/or your subscription has since expired and/or the machine's not been kept fully-patched at Windows Update, don't waste your time with any of the below: Format & reinstall Windows. A Repair Install will NOT help!
Microsoft PCSafety provides home users (only) with no-charge support in dealing with malware infections such as viruses, spyware (including unwanted software), and adware.
Also available via...
Consumer Security Support home page
1. See if you can download/run the MSRT manually: http://www.microsoft.com/security/malwareremove/default.mspx
NB: Run the FULL scan, not the QUICK scan! You may need to download the MSRT on a non-infected machine, then transfer MRT.EXE to the infected machine and rename it to SCAN.EXE before running it.
2a. WinXP => Run the Windows Live Safety Center's 'Protection' scan (only!) in Safe Mode with Networking, if need be: http://onecare.live.com/site/en-us/center/howsafe.htm
2b. Vista or Win7=> Run this scan instead: http://onecare.live.com/site/en-us/center/whatsnew.htm
3. Now run a thorough check for hijackware, including posting requested logs in an appropriate forum, not here.
Checking for/Help with Hijackware:
**Chances are you will need to seek expert assistance in http://spywarehammer.com/simplemachinesforum/index.php?board=10.0, http://www.spywarewarrior.com/viewforum.php?f=5, http://www.dslreports.com/forum/cleanup, http://www.bluetack.co.uk/forums/index.php, http://aumha.net/viewforum.php?f=30 or other appropriate forums.**
If these procedures look too complex - and there is no shame in admitting this isn't your cup of tea - take the machine to a local, reputable and independent (i.e., not BigBoxStoreUSA or Geek Squad) computer repair shop.