Large 2gb PST Files are created by the Mail source agent, and the error "MAPI_E_DISK_ERROR (Personal Folders)" is seen in the log file
Max PST Size is Set to a value less then 2gb.
Large Attachments or files in an inbox can cause the PST to balloon in size. These probably are messages in the Sent Items Folder that the user attempted to send, due to the large size. The PST's Stop at 2gb as that is the Size Limit for a PST.
7/22/2011 5:14:36 AM CMessage::CopyToPST Error -2147287015 An error occurred during a seek operation. File: 'util.hpp' Line: '89' (Subject: 'System Notification from fcrnaf001 (WEEKLY_LOG) INFO', SourceKey: 'F8A3D678FDFFC14DA336FD4D96CDA38D000000DF3AD0')
7/22/2011 5:18:42 AM CMessage::CopyToPST Error -2147221226 The file D:\QMMEx\Aelita Exchange Migration Wizard\Mail Source Agent\PST\FEB20358FF0B0149A6AE88974A1870F9.PST could not be accessed. - MAPI_E_DISK_ERROR (Personal Folders) Low level error: 0x83 File: 'aeCopyMsg.cpp' Line: '1669' (Subject: 'Cluster Notification (PERFORMANCE DATA) INFO', SourceKey: 'F8A3D678FDFFC14DA336FD4D96CDA38D0000015F507B')
The Large attachments must be cleaned from the users mailbox. Enabling extended logging on the source agent will help identify the problematic messages.