I have run a preupgrade check on a SP2007 database to identify issues prior to upgrading to SP2010. The report shows a lot of messages for missing webparts. The strange thing is that I cannot identify these webparts. The message looks like:
WebPart class [293e8d0e-486f-e21e-40e3-75bfb77202de] is referenced  times in the database [sharepoint-3], but is not installed on the current farm....
When I run a TEST-SPCONTENTDATABASE command on the SP2010 environment I get similar output. I have also downloaded the SP2007Migration.console.exe from CodePlex which takes the output of the TEST-SPCONTENTDATABASE from the SP2010 environment and runs that on the SP2007 environment to fetch all the sites/pages/webpart names etc.
Still the referenced web part issues relate to many sites and have a blank title. I have checked the sites to see if they have errors on the SP2007 environment but there are none. I have even mounted the database to SP2010 and after the migration the sites are looking fine. (So what are we talking about? haha)
Question is: what is the easiest way of identifying the webparts name, title, assembly etc as I have no clue where the issues are coming from. I need to know if I can safely ignore those like old references in the database which are perhaps from SP2003?