How to fix Error 4302 on Windows Server 2025 / Windows 11

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Why This Error Happens

Error 4302 occurs when a RESTORE DATABASE or RESTORE LOG statement combines the WITH ONLINE option with another option that SQL Server’s online restore engine cannot process simultaneously, such as NORECOVERY, STANDBY, REPLACE, or certain MOVE configurations used during a piecemeal restore. Online restore requires the primary filegroup to remain accessible while secondary filegroups are restored, and options like NORECOVERY force the entire database offline, which directly contradicts that requirement. This is typically a syntax/logic conflict in the T-SQL script rather than a permissions or corruption issue, often introduced by automated backup/restore scripts that were not updated for online restore scenarios.

Step-by-Step Resolution Guide

Step 1: Identify the Conflicting Option in the Restore Script

  • Open the T-SQL script or SQL Server Agent job step that triggered the error.
  • Look for WITH ONLINE paired with NORECOVERY, STANDBY, or REPLACE in the same RESTORE statement.
  • Check SQL Server Error Log (C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\ERRORLOG) for the exact %ls value substituted into the message — this tells you precisely which option conflicted.

Step 2: Remove or Replace the Conflicting Option

  • If performing a piecemeal/online restore, remove NORECOVERY and allow the restore to default to RECOVERY for the primary filegroup, since ONLINE already keeps the database partially available.
  • If you intended to leave the database in a non-recovered state for further log restores, drop the ONLINE keyword instead and perform the restore offline.
  • Example corrected syntax:
RESTORE DATABASE SalesDB
FILEGROUP = 'FG_Secondary'
FROM DISK = 'D:\Backups\SalesDB_FG.bak'
WITH ONLINE;

Step 3: Re-Sequence Multi-Step Restores

  • If your script restores multiple filegroups or logs in sequence, ensure only the final statement in the chain uses RECOVERY (implicit default) and intermediate steps use NORECOVERY without the ONLINE keyword.
  • Separate the online filegroup restore commands from any command requiring NORECOVERY/STANDBY.

Step 4: Reissue the Command and Monitor

  • Run the corrected script in SQL Server Management Studio (SSMS) connected to the Windows Server 2025 / Windows 11 instance.
  • Watch the Messages tab for confirmation: RESTORE DATABASE successfully processed X pages...
  • Confirm no Error 4302 or related errors (4303, 3015) appear in the output.

Alternative or Verification Steps

  • Run SELECT state_desc, is_in_standby FROM sys.databases WHERE name = 'SalesDB'; to confirm the database is in ONLINE or appropriate RESTORING state after the fix.
  • If the conflict persists, perform the restore fully offline (drop ONLINE entirely) during a maintenance window, then bring the database back online manually with ALTER DATABASE SalesDB SET ONLINE; once all filegroups are recovered.