How to fix Error 3175 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: SQL Server Error 3175 – “RESTORE FILEGROUP Was Specified”

Why This Error Happens

Error 3175 occurs when a RESTORE command specifies a filegroup that conflicts with the recovery model or backup type being used, such as attempting a partial filegroup restore on a database that requires a full sequence first. This typically happens because the primary filegroup or other required filegroups haven’t been restored yet, or the backup set referenced doesn’t actually contain the named filegroup. It can also surface due to corrupted backup media, mismatched LSN (Log Sequence Number) chains, or an incorrect WITH PARTIAL / WITH NORECOVERY sequence in the restore script.

Step-by-Step Resolution Guide

Step 1: Verify the Backup Set Contents

  • Run RESTORE FILELISTONLY FROM DISK = 'C:\Backups\YourDB.bak' to confirm the exact filegroup names contained in the backup.
  • Cross-check the filegroup name in your RESTORE DATABASE ... FILEGROUP = '%ls' command against this output—names are case-sensitive and must match exactly.
  • Confirm you are not referencing a filegroup from a different database backup by mistake.

Step 2: Restore the Primary Filegroup First

  • Ensure the PRIMARY filegroup has been restored before attempting to restore secondary filegroups, as SQL Server 2025 enforces this sequence strictly.
  • Use the correct syntax: RESTORE DATABASE YourDB FILEGROUP = 'PRIMARY' FROM DISK = 'C:\Backups\YourDB.bak' WITH NORECOVERY, PARTIAL;
  • Follow up immediately with the secondary filegroup restore in the same NORECOVERY chain.

Step 3: Check the Recovery Model and LSN Chain

  • Open SQL Server Management Studio (SSMS 21) and run SELECT name, recovery_model_desc FROM sys.databases WHERE name = 'YourDB'; to confirm the database is in FULL or BULK_LOGGED recovery, since partial/filegroup restores are not supported under SIMPLE recovery.
  • Validate that no log backups are missing by running RESTORE HEADERONLY FROM DISK = 'C:\Backups\YourDB_log.trn' and comparing the FirstLSN/LastLSN values against your full backup’s CheckpointLSN.
  • If the chain is broken, you must restart the restore sequence from a valid full backup.

Step 4: Rebuild the Restore Script with Explicit File Paths

  • In Windows Server 2025, confirm the SQL Server service account has read/write access to the backup folder (C:\Backups\) via File Explorer > Properties > Security.
  • Rewrite the script using WITH MOVE clauses to map logical file names to physical paths, avoiding ambiguity that can trigger filegroup errors:
  RESTORE DATABASE YourDB
  FILEGROUP = 'SecondaryFG'
  FROM DISK = 'C:\Backups\YourDB.bak'
  WITH MOVE 'SecondaryFG_Data' TO 'D:\SQLData\SecondaryFG.ndf',
  NORECOVERY;
  • Execute the full restore chain (data + log backups) in one uninterrupted batch to avoid state mismatches.

Step 5: Finalize Recovery

  • Once all required filegroups and logs are restored, run RESTORE DATABASE YourDB WITH RECOVERY; to bring the database online.
  • Check sys.master_files to confirm all filegroup states show as ONLINE rather than RECOVERY_PENDING.

Alternative or Verification Steps

  • Verify success by running SELECT name, state_desc FROM sys.databases WHERE name = 'YourDB';—the state should read ONLINE, and querying tables within the restored filegroup should return data without error.
  • If the error persists, use DBCC CHECKDB('YourDB') WITH NO_INFOMSGS after recovery to rule out underlying corruption, or restore the entire database (all filegroups) in a single operation instead of a partial/piecemeal restore.