PCTools isn't a suite, (anti-virus, anti-spyware, firewall), that we ever recommend. What I see is that Malwarebytes anti-malware is not working, and that is often caused by malware. malware will often do it's best to disable anti-malware and anti-virus scanners.
I think that the same problem is causing the ZAC browser from working, and in fact you have mentioned search redirecting issues, so that is another clue.
I would get MBAM working. Did MBAM install properly and just doesn't run, or did it not even install properly?
If it did install, you have two choices. Before trying either, I would disable XP's System Restore. Malware can hide in the SR files and are not easily removed from there. How to disable System Restore;
Don't use Microsoft's 'Fix' if it is offered. Follow the manual instructions. Re-enable System restore immediately.
1] Run it from XP's Safe Mode. It should have enough generic anti-malware definitions in the basic install to run a full scan. Let MBAM find and quarantine anything it finds.
When the scan is finished, reboot back into Normal Mode and see if MBAM will work properly. If so, open it, update it's definitions, and run another full scan.
2] Or, rename MBAM's executable file and run it from Normal Mode anyway. Find mbam.exe on this computer, (it normally installs in C:\Program files\Malwarebytes Anti-malware folder), right click the file, and rename it to something else, eg, gogetem.exe. Double click that file to run MBAM and see if it works. If it does, immediately update the definitions then run a full scan.
Either way, once MBAM has finished scanning I would also visit an online scanning service like Trend Micro's Housecall at;
I hope that helps.
I am running XP Media Center, Dell Dimension 9100. Recently, one of my programs (ZAC Browser - a special web browser for kids w/ autism) suddenly stopped working. I try to open it, it'll show up in "processes" in the task manager for a second or two, then it's gone. It never shows up in the programs tab. I haven't made any significant changes to the system since the last time it was used. I've tried uninstalling, reinstalling, rebooting, system restore and various registry fixes I've found in other forum threads. So far, no luck.
Everything else seems to be working fine, with one exception. I'd tried to install Malware Bytes (?) in hopes of tracking down the search redirect issues I've been having (different subject), and that program would not run, either. Behaved exactly the same way.
I'm using PCTools SpyWare Dr. It runs regularly, but so far I've only caught tracking cookies - nothing significant.