Rated 5 out of 5 stars

by mflowers on Feb. 12, 2010 · permalink

I was having trouble with Thunderbird 3 not being compatible with this addin. I had to amend the INSTALL.RDF file in the XPI (I opened it as a ZIP file, which it essentially is). I went to the string {3550f703-e582-4d05-9a08-453d09bdfdc6} and in the following maxVersion tag changed the version to 4.0a1 (to give myself some future proofing!). I then installed again successfully. (Thanks to osian78 on http://getsatisfaction.com/mozilla_messaging/ for this advice)