I too have had repeated problems installing Compare an occasionally others (XMLTools) but it usually seems to be a problem downloading them. If I install manually that works. I do system administration and have lots of VMs. I routinely install Notepad++ and Compare plugin. Lately I have noticed the plugin installation complaining about not being able to validate the *.dlls associated with various plugin installations. Just today, I was told after installing XMLTools that a newer version than 2.4.6 (which I just installed) was available (2.4.7) but when I checked it said i had the latest.