Development edition invalid licence

["WManns" <webforumsuser@xxxxxxxxxxxxxx>]

I am having problems getting the development edition of coldfusion to work. I 
had installed the trial edition some time ago on our test server which had 
reverted to the developer edition after 30 days. This was fine, but I wanted to 
re-install coldfusion as the enterprise edition.

 I have now installed coldfusion 3 times as the developer edition on this 
machine and each time, though the install is succesfull I get an error message 
saying "Your server key is invalid".

 How can I get the developer edition to work on this machine?

 Thanks