Backup Exchange 2007 - B2D GRT Error

My Setup:

Server 1 (Physical server) - Back exec 2010 R3 on Windows server 2008 R2.

Server 2 (Virtual server) - Exchange server 2007 SP2 on SBS 2008.

Issue : Recently upgraded to BE 2010 R3, added all updates and installed remote agent to exchange server.  All seems to work well until I try backup exchange mailbox and public folder using GRT and Back up to disk folder.  I get error below. 

- Backup direct to tape, works fine. 

- If i turn of GRT, backup completes okay no errors.

I have tried registry fix on Exchange server , doesnt work.  Only other option to to turn off GRT as in http://www.symantec.com/business/support/index?pag... how do I restore individual mail items.

Question:
1. Anything else I can try?
2. If i cant use GRT, kindly advice how to recover emails.

Thanks

Errors:

Final error: 0xe0000396 - Cannot extract mailbox messages from the Exchange backup. Review the job log for more information. Final error category: Resource Errors For additional information regarding this error refer to link V-79-57344-918

V-79-57344-918 - Unable to complete the operation for the selected resource using the specified options. The following error was returned when opening the Exchange Database file: '-546 The log file sector size does not match the sector size of the current volumn. '

links :

Registry fix -> http://www.symantec.com/business/support/index?pag...