Try following steps to get around this error message for importing / opening the WEBI Reports
1) Import document from CMS using Webi Rich Client logged into live server
2) Open document in Webi and use Save As option to overwrite original document.
3) When saving use the 2 options Save for all users and Remove document security (both ticked)
4) Log into Test server using Webi Rich Client, this logs off live and closes document.
5) Opening document in Webi should now be successful
Note: You need to save the reports with save for all users, only then you can open this report in another environment.
When opening the Webi documents in another CMS
1) First open it in the Old CMS.
2) Save it without Security (it's a little tick box at the bottom left) and for everyone (another tick box).