List members of a nested group

OK, I want to list the members of 2 groups. Each group has nested groups :

GroupA has 96 nested groups. This command works ok :

dsquery group -name "List_A" | dsget group -members -expand -c | dsget user -display -email -c >>c:\usersA.txt

Group B has 197 nested groups. This command fails :

dsquery group -name "List_B" | dsget group -members -expand -c | dsget user -display -email -c >>c:\usersB.txt

I get the error dsget failed:'Value for traget object for this command has incorrect format'

My group names are correct and the command syntax is the same - the only difference is the amount of nested groups.

Has anyone seen this before ?

Thanks

Dan