Cupertino, Calif.--AdForce Inc., the ad-serving subsidiary of CMGI Inc., has closed. The company laid off all of its 155 employees. Andover, Mass.-based CMGI bought AdForce in September 1999 in a stock deal valued at $500 million. The news came as CMGI announced that its fiscal third-quarter 2001 loss was $963.3 million, compared with a year-earlier loss of $428 million. CMGI said it will end fiscal 2001 with $785 million in cash.