Troubleshooting problems signing in Zoom


  • This article provides solutions to the two common problems regarding signing in Zoom.

“Bad Request - Header Field Too Long”

Graphical user interface, text, application

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  • Please consider clearing all the browser temporary file, history and cache of your default browser. Then restart the browser, and sign in Zoom, i.e. (or in mainland China) and/or access the meeting link again.
  • Or, use a new "private/incognito/inprivate window" to visit the meeting link and/or sign in Zoom via "CUHK Login". Instruction on opening "private/incognito/inprivate window":

“Something went wrong while you tried singing in with SSO”

Graphical user interface, text, application, email

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Please take the following steps to check if your ZOOM account is working:

  1. Launch your default web browser.
  2. Clear ALL browser cache and internet temporary files.
  3. Restart the web browser.
  4. Visit
  5. After successful login, open a new browser tab, visit (or in China).

For staff: if you rejoin CUHK and have set up a new email alias, the change of email address will cause problem regarding the SSO sign in. You need to contact us ( for help.

You may then follow to join ZOOM meetings restricted for CUHK users.

If you still encounter the problem after taking the above steps, please let us ( know. We will check if your account is locked due to too many failed login attempts. The current locking mechanism is 30 minutes for 5 failed attempts.

Enquires about 2FA (DUO Two Factor Authentication)

Incorrect user ID or password

  • Please refer to ITSC Website: Log in through CUHK Login Page (3. The login page keeps saying "Incorrect user ID or password. Type the correct user ID and password, and try again".)
  • If you still have question, please contact the support team at ITSC Service Desk (Account, Email & Access > General Enquiry > Computing Accounts and OnePass Password). 

Should you have further questions, please contact us at / ITSC Service Desk (