400 - 401 error when trying to connect API in Synapse

I am having trouble connecting the Companies House API in my Synapse Pipeline.

The steps I have made so far include:
Source - Rest API

  1. base URL: https://api.company-information.service.gov.uk/ or +company/ or +company/company_number or https://api.companieshouse.gov.uk/.
  2. Authentication:
    a. Basic - provide my username and password from companies house account
    b. Anonymous - no username, password
  3. Auth Headers:
    a. APIKey
    b. X-API-Key
    c. Authorization (available only when selecting the Anonymous Authentication)
  4. No Annotations, Parameters, Advanced Settings.

The connection test is successful every time but I can’t figure out what is missing to get the 200 code that is needed.
I am getting 400 error with {“error”:“Invalid Authorization header”,“type”:“ch:service”}
or 401 error with message {“error”:“Empty Authorization header”,“type”:“ch:service”}
Can you please point out if there is any step wrong and what should be used instead of what I am inputting?

1 Like

Hi there, I am having the same problems as you describe.
I wonder if you managed to overcome them and how did you do that.

Hi, not sure if you solved this. I have not used Synapse, but looking at my connection in other tools you could try:
Authentication Basic - use the KEY as username, no password
In my application this then automatically adds the authorization key (which is "Basic " followed by key_transformed_from_hex).
APIKey and X-API-KEY are not needed.

Hope this helps!