Im trying to do a migration from Exchange 2003 to Exchange 2010 SP1 across forests.

I have already set up the DNS and i can ping the servers from each DC, i have also already created the trust.

The next step i am trying to do is using Prepare-MoveRequest.ps1

Prepare-MoveRequest.ps1 -Identity darran@darranpage.local -RemoteForestDomainController test.darranpage.local -RemoteForestCredential $RemoteCredentials -LocalForestDomainController mat-crm.test.org -LocalForestCredential $LocalCredentials
The code is above what I am using, i keep getting the following back

Source Domain controller unavailable or authentication failed.
At C:\program files\microsoft\exchange server\v14\scripts\Prepare-MoveRequest.ps1:1122 char:14
+ throw <<<< "Source Domain controller unavailable or authentication failed."
+ CategoryInfo : OperationStopped: (Source Domain c...ication failed.:String) [], RuntimeException
+ FullyQualifiedErrorId : Source Domain controller unavailable or authentication failed.
Ive searched the internet and i cant see where im going wrong.