ERROR CODE 0X80040017

purchased approx 2 year old hp computer from work. os is xp home edition. updates are not current. Computer worked fine for approx 1 week. Now when booting up the following message appears “A problem is preventing Windows from accuratley checking the license for this computer. Error Code 0x80040017.” After clicking “ok” computer logs off. This happens on all users of this pc. Please help-Thank You