Where did you put this line?
Also, which version of AD plug-in do you use?
BTW, I think the attribute is named userPrincipalName, not userPrincipleName as in your code.
After using the workflow which creates the user (its output is AD:User), I create a scriptable task which takes this new user and run on it the setAttribute().
My plug-in version is: 184.108.40.20677446.
And yes, I wrote it right in the code, just wrong copy paste.
Any new idea?
Tried it in my environment, and it seems to work fine (I have version 3.0.7 of AD plug-in).
If possible, could you try with some of the newer versions of the plug-in available at https://communities.vmware.com/docs/DOC-25138 ?