User information never gets written to the State server flat files held locally on the cluster server.
Assumption: This occurs on a portal that was imported.
1. In the PMC, expand the Administration node.
2. Open the Configuration Library.
3. Double-click each of the cache types below.
4. Click the Properties tab for each and verify that the Value of the Root Directory is correct for each.
Most likely the paths were not updated when the portal was imported and the paths are not correctly pointing to the location of the state server.