SQL Server 2012 Express backup database failure

Question

I am trying to backup a database I have created in SQL Server 2012 Express. I right click the database -> tasks -> backup and assume normal defaults.

The error I get is then this:

TITLE: Microsoft SQL Server Management Studio
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Backup failed for Server 'JAMIE-PC\SQLEXPRESS'.  (Microsoft.SqlServer.SmoExtended)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=11.0.2100.60+((SQL11_RTM).120210-1917+)&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&EvtID=Backup+Server&LinkId=20476

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ADDITIONAL INFORMATION:

System.Data.SqlClient.SqlError: Cannot use the backup file 'C:\backup.bak' because it was originally formatted with sector size 4096 and is now on a device with sector size 512. (Microsoft.SqlServer.Smo)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=11.0.2100.60+((SQL11_RTM).120210-1917+)&LinkId=20476

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BUTTONS:

OK
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This does not mean an awful lot to me but looks potentially like a FAT32/NTFS style issue !? despite that seemingly distinctly detached from SQL Server 2012! The version I am running is 11.0.2100

Answer 1

Ah - turns out I had added a new backup file to the list but had not removed the existing one - and because the existing file was above the new file it was failing with the error before writing to the new backup file.

Removing the existing backup file from the list and adding a fresh one in the backup folder of the SQL server installation directory solved the problem! Thanks to Raphael for helping me spot it.