I have been using A-Squared Free for quite some time and have always liked the program. However, after a scan on March 27, RPCRT4.dll was marked for removal after reboot. When this was done, the computer was unable to boot into Windows XP. I was not even able to access Safe Mode for System Restore. I had to do a complete recovery in order to get my computer working again, and some files were lost. According to this article, RPCRT4.dll is an essential Windows file that should not be removed. This is a warning to others to beware!