Exchange 2010 upgraded to SP3 from SP2 - Mailbox Failing to Mount

Hello, My problem is that exchange has been upgraded from SP2 to SP3 on a SBS2011 server and the Mailbox Database is failing to mount. The Installation was successful and rebooted ok afterwards. However

When I try to mount the Mailbox Database, I receive the following error message:

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Microsoft Exchange Error
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Failed to mount database 'Mailbox Database'.

Mailbox Database
Failed
Error:
Couldn't mount the database that you specified. Specified database: Mailbox Database; Error code: An Active Manager operation failed. Error The database action failed. Error: Operation failed with message: MapiExceptionCallFailed: Unable to mount database. (hr=0x80004005, ec=-1032)
. [Database: Mailbox Database, Server: SERVERNAME.DOMAIN.local].

An Active Manager operation failed. Error The database action failed. Error: Operation failed with message: MapiExceptionCallFailed: Unable to mount database. (hr=0x80004005, ec=-1032)
. [Database: Mailbox Database, Server: SERVERNAME.DOMAIN.local]

An Active Manager operation failed. Error Operation failed with message: MapiExceptionCallFailed: Unable to mount database. (hr=0x80004005, ec=-1032)
. [Server: SERVERNAME.DOMAIN.local]

MapiExceptionCallFailed: Unable to mount database. (hr=0x80004005, ec=-1032)

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OK
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Can anybody provide me with a solution or what I need to do next?

Thanks in-advance