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#502 – fatal: Authorisation Failure (when submitting accounts to Companies House)

When attempting to file to Companies House, you may get the error message #502 – fatal: Authorisation Failure. If you receive this error. it means that one of the following entries is incorrect or missing. Please check all the details carefully and re-enter them where possible. Delete any spaces appearing at the end of an entry.

  • Country of Incorporation – make sure the correct type is selected:
    • EW – England and Wales company
    • SC – Scottish company
    • NI – Northern Ireland company
    • R – Northern Ireland company registered before the partition of Ireland in 1922
    • OC – other England and Wales company (only used for LLP cases in liquidation)
    • SO – other Scotland company (only used for LLP cases in liquidation)
    • NC – other Northern Ireland company (only used for LLP cases in liquidation).
  • Company registration number – if this is wrong, change it on the accounts.
  • Company Authentication Code a six-character alphanumeric code which is specific to the company you're filing. Please note this is case sensitive and is usually expected to be capital letters. 
  • Email address – this needs to match the one you used to register for the Presenter Identifier and Presenter Authentication Code.
  • Presenter Identifier and Presenter Authentication Code – these are both provided by Companies House and aren't the same details as you use to log in to their website. The Presenter ID is 11 digits long and starts with 000 and ends in 000, this contains a mixture of numbers and letters.  If you don't have these yet, fill in the application form and email it to Companies House. Please note that the Presenter Code is case sensitive and is usually expected to be capital letters. 

If you have attempted the above and are sure that the entries are correct, our support team will be able to review the submission log file and compare the data expected to the data contained within the file. To do this, please open the client in Accounts Production for the relevant accounting period, click on Check and Finish, locate the most recent submission attempt, right click on this and select Send to TaxCalc (as shown below). 

Once you select this a pop up box will appear where you will need to input the entries you are inputting into TaxCalc for the below information:

  • Company type 
  • Company registration number
  • Company Authentication Code 
  • Email address 
  • Presenter Identifier
  • Presenter Authentication Code