AdminLib GetBTSMessage: hrErr=80070002; Msg=The system cannot find the file specified.;I found this to be a result of Network DTC not being configured correctly. The following needed configuring on both the BizTalk server and the remote SQL Server 2005 machine.
Goto Component Services / My Computer / Properties / MSDTC Tab / Security
Configuration and Enable Network DTC Access
Enable Network DTC Access
Allow Remote Clients
Allow Inbound
Allow Outbound
Mutual Authentication Required
Enable Transaction Internet Protocol (TIP) Transactions
I found the fix here