[jcifs] InvalidOperationException

[Shane]

Gidday,

Have just started using jcifs 1.1.9 for the first time and i'm getting an 
SmbException InvalidOperation on workgroup or server while trying a copyTo() 
operation.

What would be the likley cause of that error?

I have confirmed that the source and destination paths exists and the user, 
password and server names are correct and have permission to copy files.

Thanks in advance
Shane