[Steve Turner, Jan 8, 2007]
Modified Jan 23 - Issue resolved. It appears the DNS field for a web project must be unique, and is used by the virtualization to form the preview URL.
For the first web project I created, I used DNS name 'localhost'. I imported the sample Alfresco web app into this project.
For the second web project, I also chose 'localhost' as the DNS name, as it was also going to be running on my machine. I proceeded through the Create Web Project Wizard to the end, whereupon I got this error message:
"A system error happened during the operation: AVMStore exists: localhost"
So two things - the validation check for duplicate DNS name should take place on the first page of the wizard, when you fill in the DNS Name and hit 'Next'.
Second, It's not clear to me what exactly DNS Name is for in this context. Does it have to be a valid name for my machine, or can it be anything?