You'll find that it's against forum policy to offer advice as to how to circumvent group policies dictated by your employer. It is probable that such policy was implemented to offer additional security to devices they own. For this reason, you're better off taking this to issue to your employer's help desk. If there's a reason to back up company files, they should be the ones handling this.
Once a month, I backup my laptop's files to an external hard drive. But, about three weeks ago, my company enabled Group Policy to where none of us employees are able to plug external hard drives into our USB ports.
Is there a way of overriding this policy?
If not, is there a way that I can find the local administrator password, so that I can login without being on the domain, plug in my external hard drive, and back up my files?