Just a a very quick tip for those of you whom might come across this problem when trying to move an Exchange 2007 SCC Clustered Mailbox Server instance over to the passive node:

[PS] C:\>Move-ClusteredMailboxServer -id lab-scccms-01 -TargetMachine lab-sccexnd-02 -MoveComment "Reboot" -Confirm:$False
Move-ClusteredMailboxServer : Cluster Common Failure Exception: The cluster node was not found. (Exception from HRESULT: 0x800713B2)
At line:1 char:28
+ Move-ClusteredMailboxServer  <<<< -id lab-scccms-01 -TargetMachine lab-sccexnd-02 -MoveComment "Reboot" -Confirm:$False

After checking, and double checking my configuration (which initially seemed to be fine) I found that from within the Cluster Administrator the Passive node (which I was trying to move the resources to) was not a “Possible Owner” on all the Resources within the Exchange Cluster – after I added it – the move process worked fine.