I had to reinstall the latest version because it slowly ended up freezing my machine. I don't know whether this is an inherent problem of this version or because or incompatibility issues. After reinstalling and rebooting things are back to normal. Poor box, it was so stressed. Running here (software stuff): 1. AntiVir 2. Win Defender 3. Ad-Aware In the previous version I was using Avast instead and other utilities and never had an issue. So my toss would be between the last version being buggy or Sandboxie and AntiVir are kind of an unhappy marriage. Any ideas? Otherwise I was thinking of swapping to these other free alternatives: 1. Fortres Virtual Sandbox 1.0 http://www.fortresgrand.com/products/free/vsb_free.htm) 2. GeSwall. I read some users having problems with it. 3. VMware. http://www.vmware.com/ 4. QEMU. http://fabrice.bellard.free.fr/qemu/about.html 5. Microsoft Virtual PC http://www.microsoft.com/windows/virtualpc/default.mspx 6. Xen. http://www.xensource.com/xen/downloads/index.html 7. OpenVZ. Unfortunately only for Linux boxes. http://openvz.org/ 8. Parallels Not free though. http://www.parallels.com/ 9. DiscoverStation. As above. http://userful.com/products/discoverstation 10. And others mentioned in Wikipedia: http://en.wikipedia.org/wiki/Comparison_of_Application_Virtual_Machines http://en.wikipedia.org/wiki/Comparison_of_virtual_machines Which free product would you recommend me? I'll probably shoot for Virtual PC but I'd like to hear your opinions first. Cheers.