launch URL does not open Outlook

[mfstuart at cox.net]

Hi all,
I have a script that uses "launch URL theURL" to open Outlook, but sometimes it doesn't open it.
theURL = mailto:mark at somecompany.com?Subject=blah blah blah&Body=This is the message body text, with sometimes lots of text. And sometimes a small amount of text.

I think the amount of text in the body doesn't matter, as in one test the body text was only a few sentences, and Outlook didn't launch.

I've tried it on Outlook 200 and 2003 - same results.

Anybody with some ideas on this as to why Outlook doesn't open?

Regards,
Mark Stuart