We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

I see this message when trying to open email. What does it mean?

more options

Those are all the details I have. I can see emails on Explorer but not on Firefox which I prefer. This is the message that appears :

Bad Request Your browser sent a request that this server could not understand. Size of a request header field exceeds server limit. Cookie: OAX=GAL/BEl4030ACR/8; s_vi=[CS]v1|4978D37E0000074A-A290B540000006C[CE]; RMAM=01cen10_1004.4aD7I9SG|cen9_1004.4aDIGaJm|; edit

Those are all the details I have. I can see emails on Explorer but not on Firefox which I prefer. This is the message that appears : Bad Request Your browser sent a request that this server could not understand. Size of a request header field exceeds server limit. Cookie: OAX=GAL/BEl4030ACR/8; s_vi=[CS]v1|4978D37E0000074A-A290B540000006C[CE]; RMAM=01cen10_1004.4aD7I9SG|cen9_1004.4aDIGaJm|; edit

All Replies (1)

more options

Sounds as though you have too many cookies for the site that hosts your email.

If you right-click a page on the site, choose View Page Info, then the Security tab, you can click "View Cookies" and remove some or all of them. Make sure to save any draft messages or other work before doing this, because it probably will log you out.

Does that resolve the issue?