Laptop losing connection to the domain

For the past few days now everytime a specific employee comes into work, she cannot access her account from her workstation(Win XP Pro SP3).

She gets the “Client is not able to connect with domain or Domain controller is not available.” message.

So far, the solution has been to just remove the computer from the domain, then rejoin it, which is easy enough.

But it’s hampering production and taking both the IT department and Sales away from their more important tasks at hand.

any ideas why the client would have this problem every morning?