We recommend using Visual Studio 2017

Sharing is not supported in Team Foundation Source Control

Team Foundation source control does not support sharing, therefore, the converter cannot migrate the share links between shared files. You may have to reorganize files that are shared files across projects. During migration, shared files are migrated by creating a version in the destination folder by using the same content as the version of the file at the time when you started sharing. From then onwards, the changes that were made to the shared file are replicated to both locations.

Sharing is a pre-condition of branching. Therefore the converter cannot map a Visual SourceSafe branch to a Team Foundation source control branch. The migration of a shared file gives you a replica of the file to the destination folder. Migration of branch events means that the changes that were made to a shared file are not replicated to both locations any longer. Therefore, the changes to any branch are migrated to the respective copy in Team Foundation.