DLO Error outlook.pst file

Hi all

I keep getting the folloing error

23/09/2013 15:57:37 - Backup - c:\documents and settings\userl\local settings\application data\microsoft\outlook\outlook.pst\Drafts\000000005CA9FC64574ED0419388C23C3E89B0A0249C3300 - Mapi resource error.  This could be a network, disk space, or out of memory problem.  Retry the operation. (8004010f) (MAPI_E_NOT_FOUND )  - http://www.symantec.com/business/support/index?pag...

Of cource i have checked the Network - as all other files are copied

the disk space - has ample of GB free

and the memory is fine..

Thank you for your help

Regards

Mark