The company Registration number entered in the Accounts does not match the registration number on the CT600

Article ID: 1171
Last updated: 31 Mar, 2017

If you receive this error message it means that either the downloaded file is corrupt or it contains special characters that HMRC can't read.

Corrupt file

If you opened the downloaded file and then used File > Save As, it might be corrupt. The correct way to save a downloaded file is to convert it through your browser as follows:

  1. Download the file using your normal browser and save it in your Downloads folder:
    • Internet Explorer: click on Save
    • Chrome: saves automatically
    • Firefox: click on Save
  2. Go to your Downloads folder using the relevant shortcut:
    • Windows: Ctrl + J
    • Mac Chrome: Cmd + Shift + J
    • Mac Firefox: Cmd + J
    • Mac Safari: Cmd + Option + J
  3. Copy/cut and paste the file from the Downloads folder into your desired location.
  4. Attach the accounts.

Special characters

Change any special characters so that HMRC can read the file. For example, change café to cafe.

Article ID: 1171
Last updated: 31 Mar, 2017
Revision: 7
Views: 1026
This article was:  


Also listed in
folder Tax Return Production -> CT600 Corporation Tax Return