The UK version of Google's payments service Google Checkout has been foundering for two days, and is currently completely offline, with no explanation from the company.
US users are also reporting problems on Twitter.
The dominant search engine launched its payments service in 2006 in a direct attack on PayPal.
"I too have been having this problem for a couple of days," said "InToKnit" in a typical gripe today.
"As far as I know unlike Paypal they have no technical support via the phone and we just have to hope someone is doing something. If it carries on today I shall remove Google Checkout as an option for payment until it's fixed."
Some users claimed Google had told them it had fixed the glitch.
A Google spokesman said he would look into the ongoing problems. ®