"Late this morning, an e-mail software issue started to cause delays in the sending and receiving of AOL e-mails for our members and AOL.com users," AOL spokesman Nicholas Graham said in a statement. "We are in the process of implementing a fix and investigating its cause. All e-mails sent by AOL members and Internet users during this temporary hiatus will be delivered to e-mail inboxes. During this time, some e-mails will be able to be sent and received intermittently."

The e-mail outage affects the company's paid AOL.com members and users of its free AIM.com e-mail services.

The company expects to repair the software problem, which is still being diagnosed, by later this afternoon, he said.

AOL, a division of New York-based Time Warner, says it has nearly 27 million members worldwide, including about 20 million members in the U.S.