Restore database error SQL Server 2008

I got this error when trying to restore AX database in my local PC :

Cannot open backup device 'c:\path\backupdbname.bak'. Operating system error 5(failed to retrieve text for this error. Reason: 15105)

It turns out that the sql server service account is Network Service, and this account does not have access to the backupdbname.bak file.

To solve this, right click the backup file, go to security tab, click edit. Then add the Network Service account to have read access to the file.