User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:184.108.40.206) Gecko/2009060215 Firefox/3.0.11 (.NET CLR 3.5.30729) Build Identifier: 220.127.116.11 When file(s) are selected in Windows Explorer, context menu Send To > Mail Recipient results in nothing happening with 18.104.22.168 updated automatically from 22.214.171.124; Works fine in 126.96.36.199; 100% reproducible. Reproducible: Always Steps to Reproduce: 1. Select files in Windows Explorer 2. Right click to pop up Context Menu 3. Select Send To > Mail Recipient Actual Results: Outlook pops up a window complaining about not being the default mail client. Expected Results: Thunderbird Compose window opens with selected files Attached. Solved the problem by installing 188.8.131.52 (which worked properly), and then installing 184.108.40.206 (instead of updating). 220.127.116.11 now works properly. Note: During the install of 18.104.22.168 I got an error that MapiProxy.dll was in use. I had to log off, back in, and redo the install.
This appears to be the same problem as bug 482966 against 3.0beta (now fixed).