I have a job which runs every 30 minute and takes t-log backup of the database suing Ola's script. Every Thursday and Friday at 22:45 I get an error:
11/07/2019 22:45:00,Backup,Unknown,Error: 3041<c/> Severity: 16<c/> State: 1. 11/07/2019 22:45:00,spid60,Unknown,BackupDiskFile::CreateMedia: Backup device 'B:\SDSOFT-DB\EXPRESS\LOG\SDSOFT-DB_EXPRESS_LOG_20191107_224500.trn' failed to create. Operating system error 5(Access is denied.). 11/07/2019 22:45:00,spid60,Unknown,Error: 18204<c/> Severity: 16<c/> State: 1.
I asked sysadmin to check all settings regarding NAS storage and he said that everything ok and he doesn't know what is the cause of this problem. From my side, I mapped NAS storage network path into 'B' using xp_cmdshell(SQL SERVER 2014) by the help of the following command:
EXEC xp_cmdshell 'net use B: \\192.*.*.*\DBbackups /user:<username> <password> /persistent:yes'
I would like to point out again that I get no error during the rest of the time, only on Thursday and Friday at 22:45. Maybe someone had faced with this issue before and help me to tackle this problem.