# HTTP Status Codes

WHMCS API uses standard HTTP status codes in the response header:

table
tbody
tr
th
Code
th
Description
tr
td
200
td
Success
tr
td
202
td
p
You must provide a second authentication factor to finish login.
tr
td
401
td
p
Unauthorized
p
Usually, this indicates that the username or password is not valid or the system denied the requested access.
tr
td
403
td
p
Forbidden
p
Usually, this indicates that the IP address is banned due to too many login failures or it is not whitelisted (when WHMCS API IP restriction is enabled).
tr
td
404
td
Not Found
tr
td
412
td
p
Precondition Fail
p
Usually, this indicates that Two-Factor Authentication is required or the provided Two-Factor Authentication token is invalid.
tr
td
422
td
p
Invalid input
tr
td
500
td
Internal Server Error