Split backup on SQL Server 2012

Question

I am doing a split backup such as:

BACKUP DATABASE [A] 
TO DISK = N'L:\sql_bak\A_full.bak',  
   DISK = N'M:\sql_bak\A_full2.bak',
   DISK = N'O:\sql_bak\A_full3.bak' 
WITH NOFORMAT, INIT,  
     NAME = N'A-Full Database Backup', 
     SKIP, NOREWIND, NOUNLOAD,  
     STATS = 10
GO

I get an error:

Message Executed as user: DOMAIN\\sqlserviceaccount. The volume on the device "L:\\sql_bak\\A_full.bak" is not part of the media set that is currently being processed. Ensure that the backup devices are loaded with the correct media.
[SQLSTATE 42000] (Error 3258) BACKUP DATABASE is terminating abnormally.
[SQLSTATE 42000] (Error 3013) The step failed.

In one of the blog posts I read that I can use FORMAT to resolve this issue but formatting any volume of a media set renders the entire media set unusable.

Please suggest.

Answer 1

I went to Run->diskmgmt.msc and formated the three disks manually. Created the folder sql_dat in all the three drives and then I started the backup and it ran successfully.