Classic SQL Server backup set fails with VDIRemote OpenCommunicator named pipe errors

Classic SQL Server backup set fails with VDIRemote OpenCommunicator named pipe errors

Machine-distilled from a resolved support ticket on 2026-09-28. Source ref: 476099e2e56f. Verify before relying on it.

Applies to: DS-Client backing up SQL Server using classic SQL Server backup sets (VDI based) on Windows backup source servers; version not confirmed.

Symptom: A classic SQL Server backup set completes with errors on every run, reporting a VDIRemote named pipe error such as 'The system cannot find the file specified. (VDIRemote: OpenCommunicator(...\pipe\ASIGRA_SQLBACKUP_VDI_<database>...))'. Related variants include 'All pipe instances are busy. (VDIRemote: OpenCommunicator(...))' and 'The specified network name is no longer available. (VDIRemote: OpenCommunicator(...))' or '(VDIRemote: Read data from named pipe)'. Running a synchronisation and re-running the backup does not clear the error.

Cause: Memory fragmentation on the backup source server (the Windows server hosting the SQL Server instance being backed up) prevents the VDI named pipe communication between the DS-Client and SQL Server from being established or maintained.

Resolution: 1. Restart the backup source server that hosts the SQL Server instance. 2. On that server, review and increase the page file (virtual memory) size: Control Panel > System (or right click This PC/My Computer > Properties) > Advanced System Settings > Performance > Settings > Advanced tab > Virtual Memory > Change. Note the currently assigned, minimum and recommended values, then increase the size accordingly. 3. Re-run the SQL Server backup set and confirm it completes without the VDIRemote named pipe error.