Special thanks to Richard Lacroix at Manulife Financial for supplying this notes.ini setting.
NOTDEFAULTMAILTO
Got Lotus Notes 4.6a or older and work remotely?
Then you've probably experienced Notes taking over the Mailto Protocol everytime it runs.
Having to reset the association is a pain, and having Notes try to start up when you wanted your regular email client instead is a bother, so why not fix it for good until you finally get your upgrade? (This is not supposed to be a problem in Notes 4.6.1 and above - but I wouldn't know!)
Append the following to your notes.ini and beat the protocol blues
NotDefaultMailTo=1
This was first published in October 2000