You should really have opend up a new post rather then using an existing post.

Is the password that your using for account MR-3211\administrator.

this will be the local account on the workstation, that the RunAs is being run at, if you want to use a domain account you need to put in /user:{Domain}\Administrator.

The @Error will get the error status of the Shell reference, and that has run fine, so you will get a Error 0.