Another popular mistake is to remove the sqldebugger-user from the domain which will result in
EXECUTE permission denied on object 'sp_sdidebug', database 'master'
error message.
To get around this you need to create a similar new account and configure DCOM according to "Troubleshooting the Transact-SQL Debugger" in BOL
Here's an interesting KB article.
http://support.microsoft.com/?kbid=328173
--
Frank Kalis
Microsoft SQL Server MVP
Webmaster: http://www.insidesql.org/blogs
My blog: http://www.insidesql.org/blogs/frankkalis/[/url]