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Unable to Sign in to Costco.com

Firefox Website breakages
Drew Faber replied
Drew Faber
Drew Faber

I am unable to sign into Costco.com using Firefox. I get an error message: 

    "Bad Request - Header Field Too Long
    HTTP Error 400. A request header field is too long."

Turning off all extensions didn't help. Opening a private browsing window DID work. Using Chrome DID work.

Thanks!

I am unable to sign into Costco.com using Firefox. I get an error message: "Bad Request - Header Field Too Long HTTP Error 400. A request header field is too long." Turning off all extensions didn't help. Opening a private browsing window DID work. Using Chrome DID work. Thanks!

All Replies (2)

zeroknight
zeroknight

Chosen Solution

Try "Clear cookies and site data" from the padlock icon in the address bar.

Drew Faber
Drew Faber Question owner

That worked. What an easy way to clear cookies and site data for just this site! Thanks! :)