restricted vs. unrestricted in 401k

You are light on the details, but I'd guess that this may be shares the employer has matched but as company stock. They are permitted (I think) to have a holding period during which time you can't sell those shares.

Really, most questions that have this twist - wording within one's plan, or specifics of a given plan - should be answered through the OP's benefits department or human resources. In some cases, they will refer you to the company managing the 401(k), depending on the company size, they make have people within the department capable of answering. JOE