An unusual error that sometimes occurred during a physical open of a c-tree file could cause the connection to hang when closing that file. For example, if the server was quiesced and the quiescing thread attempted to open a file, the file open could fail with error 463 (UQID_ERR), because the internal index file used for file uniqueness checking had been closed by the quiesce. That could cause a call to logoff or close the file to hang. The logic has been modified to correct this.