I can now confirm that this was an issue with the domain recognising the user I was logged in as.
The user had changed their password remotely whilst I was logged in as them (under their instruction) configuring their ODBC.
Thanks for the help Sergey!
Ben Sugden
"Remember to enjoy hunting - and that means relishing the search for the product that has never been advertised or placed handily at the front of the shop; Life begins on the uppermost shelf, avoid guide books and top 10's like the plague." - Ramsey Dukes
