A simple compatibility test:
I am using the following combo in virtual machine running WinXP:
Kaspersky Free Antivirus + Outpost Firewall Pro + Sandboxie Free + Malwarebytes Antiexploit Free + Bouncer Demo (not important here

).
This combo does not cause BSOD on my virtual machine, even if I use a very tight config of Outpost Firewall Pro (Anti-Leak set to Maximum, Firewall set to Block Most). This is not an easy job, since Outpost Firewall Pro + Avira Free can cause a BSOD in the boot peirod such that you cannot enter the system.
Now I am visiting MT with Firefox running in Sandboxie Free. So Sandboxie Free is also compatible with Kaspersky Free.
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A negative example:
Win 7 32bit (in virtual machine) + Kaspersky Free Antivirus + Comodo Firewall + Bouncer
After cleaning some malware samples, and rebooting the virtual machine, BSOD happens, and I
cannot enter the system.
Then I restore the virtual machine to the status when KFA was not installed, and the problem is solved...
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So, please be careful about the compatibility of KFA...