Awhile back, we migrated over to the Network Edition. Some users have noticed mail folders not showing in the advanced version, but can find them within the HTML version under their folder list. Once we move these "missing" folders to be subfolders under the inbox, they show in the advanced version. The culprit, or so we think, may have been that they were created on our old system with Thunderbird. We've been unable to reproduce steps to create these semi-transparent folders, but it's more than one user reporting the issue now.

Any ideas? Anyone experienced the same sort of problem? My thought was that perhaps it's some sort of folder property, but I've been unable to find tag or property that's different with these folders. Perhaps they are partially marked as another folder type (address book) and mail?