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Unable to Sign in to Costco.com

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  • Last reply by compupix

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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!

Chosen solution

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

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Chosen Solution

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

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