I cant sign in Google account and apps because iOS sent an invalid request error 400. please help to resolve this issue.

Not sure if people still have this question, but here is what worked for me (iOS 11):

Older versions of iOS (and macOS, etc.) don't use the latest authentication methods so Google blocks these less secure apps by default. However, you can bypass this by using app passwords, assuming your account uses 2-step verification:

1. Go to account.google.com
2. Go to the "Security" tab
3. Go to "2-step verification"
4. Scroll down to the bottom and click on "App passwords", then create an app password and write it down because once you close it you'll have to make a new password

Then on your device:

1. When adding the Google account, instead of selecting "Google" select "Other"
2. Fill in your information (see screenshots), but instead of putting in your regular password, put in the new Google app password. Note that the username and password is required both for the IMAP server (incoming mail) and SMTP server (outgoing mail)

Hope this helps!

This does not help and has not fixed the issue for hundreds of others, where is plan B or other help? We are stuck with what feels like no help from the professionals who built the devices. Please respond with an actual solution

I cant signin google because ios sent invalid request error 400

I cleared my History and Website Data from Safari and rebooted my ipad twice. Still, when I go into Mail, Contacts, Calendars/Gmail, as soon as I select "Re-enter Password", I get a Sign in with Google box with the alert "Access blocked: iOS's request is invalid" and at the bottom it says "Error 400: invalid_request".

Any other suggestions to allow me to enter my Gmail Password?

400 Bad Request

The HyperText Transfer Protocol (HTTP) 400 Bad Request response status code indicates that the server cannot or will not process the request due to something that is perceived to be a client error (for example, malformed request syntax, invalid request message framing, or deceptive request routing).

Erase your cached History and Website data:

Settings > Safari > Erase History & Website Data

Now restart your iPad:

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

Jacob_Fielder wrote:

This does not help and has not fixed the issue for hundreds of others, where is plan B or other help? We are stuck with what feels like no help from the professionals who built the devices. Please respond with an actual solution

The Apple Support Community (ASC) is a user-to-user technical form. Other than the site Moderators, Apple neither monitor nor participate within the Community. Contributors here are all end-users, just like you. As such comments intended for Apple will miss your intended audience.

If you need assistance from Apple, you would be best advised to contact Apple Support directly. You can contact the Support Team using the Support link at top-right or bottom-left of this page. Alternatively, you can initiate and manage your support cases from Apple devices using the excellent Apple Support App. If not already installed, the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044

Can't sign in on ipad because iOS sent invalid request error 400

Assecc blocked ios request is invalid

how to fix my ipad's invalid ios error?

Help me

I’m having the same problem. I follothe above instructions and still have the problem.

How do I fix on my iPad mini?

All my political messages from Win/Red are blocked by a 400 message saying Header is to large.

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