Haven't been able to post again today. Only changed just now. 

Just happened to me when I logged out of another ebay account and tried to switch to this one. I restarted windows and had no trouble switching to this account. 

Fingers crossed for when I go back to my main account.

I am getting exactly the same message every time I try to login to eBay

Ebay latest news, says they are working on technical issues.

There is a bad sign-in banner link.

If you sign out and use the green "You've signed out -- sign in again" banner, you may get the "Pardon our interruption" error page as I seem to, repeatably.

Try using a different link to sign back in, such as the little text link in the upper left corner of the same page.