Trouble with FTP and credit card logging functions in the US meant the European branches of the network went down, said a spokeswoman for AOL: "Unfortunately we can't section [the UK] out and we are very apologetic. It was unexpected for us. Naturally, there are outages from time to time and users tend to get good warning. This time it was unexpected."
"Modems are being bought by the truckload," she added. "We've grown exponentially, and with recent US pricing, demand has just outstripped supply."
In August this year America Online suffered a huge 19 hour outage, one of the worst ever to strike an online service provider.
AOL can be contacted by telephone on 0800-279 1234.