I backup SQL Server database and it fails BACKUP DATABASE dd TO DISK = '\backupServer\backups\dd.bak' WITH COMPRESSION, CHECKSUM, NOFORMAT, INIT , BlockSize = 65536 , BufferCount = 2200 , MaxTransferSize = 4194304 The backup size is 3TB and I have 6TB free space on bacup server. I am using backup parameters per SQLCAT whitepaper. Everything works ok when I backup to local HDD and it always fails when I backup to network share. After about 6 hours. Can't find why. Thank you. Yes. The backup over the network is fastest and saves me 3Tb of local disk space :) Thanks for pointing to the memory issue. I left 4Gb to OS and it worked!