Bad Request when processing paypal standard

Hi, I have to give up on Paypal Pro for now and fall back to Paypal Standard for lack of time. I'm getting this error below. I read that it could be cache or cookies but its happening in both Chrome and Firefox and I emptied caches. I'm sending htaccess as well in case you can tell me if that is the problem. I don't understand where the offensive header is coming from...


Bad Request

Your browser sent a request that this server could not understand.
Size of a request header field exceeds server limit.

Hope you can shine some light on this.
Thank you.

Strange. My client tested and it is working now.

I still get the error. i have tried clearing memory on my laptop (I'm traveling and only have a laptop), and it still errors for me but works for him.

I'm closing this for now. Thank you.

The error is a cookie issue in your browser because of PayPal:
www.paypal-community.com/t5/My-Feedback-...en-years/td-p/462983
Clearing the cookies of your browser should definitely fix the problem. If not, please contact PayPal's support for help as we can't do anything for you for that problem.

Regarding the SSL errors that you posted, it comes from your SSL certificate. It's either self signed, not configured properly, or signed by someone else who is not trusted either.
You need to contact your hosting company or SSL certificate provider so that they can help you get a trusted certificate configured on your server.