Can create customer account, but can't log back in

Hey folks... I'm stumped. :(

When I try to create a new customer account to test, that works fine, but when I log out and log back in, i just get a constant loop on the login page, with this error:

Error There was a security error when trying to login.
Note: If you have shopped with us before and left something in your cart, for your convenience, the contents will be merged if you log back in. [More Info]

The new customer is visible in the admin panel, but the customer can't log back in. I've tried both IE7 and FF3.6 browsers.

There's a lot of work to do on the site but before I go too far I need to get this part working. Can you help?

using zencart v1.3.9a
site: www redlinemotoparts com

https://www.zen-cart.com/tutorials/index.php?article=312

:oops: thankyou thankyou thankyou, after all the searching i did in the forums, can't believe i forgot to check the faq's. another reason to not work late at night!

Hi

I am having the same issue. Running 1.3.9b and theme 12541. Added the 'security token' info, but still the same.

Check https://www.svolta.nl/shop. Any ideas ?