0asistax is designed specifically for businesses used to submitting returns via the free HMRC service, which is now no longer available.
A 1046 error is an authentication failure that occurs when submitting a return to HMRC. It happens when a user's credentials are not recognised.
You will need to double-check your Companies House Authentication Code. This is a 6-digit alphanumeric code issued by Companies House to each company.
If you wish to file an amended return, you will need to ensure that the amendment box within the filing template has been switched to 'YES' before proceeding. This is a required step.
Your CT600 cannot be submitted because your company's accounting period has not yet ended. HMRC requires the accounting period to be fully complete before a corporation tax return can be filed, as the return must capture the total trading activity for that period.
Before submitting your return, it is important to ensure that the accounting period dates entered within the filing template accurately match the dates shown on the Companies House website.
HMRC imposes a strict 2-year time limit for amending a Corporation Tax Returns online. This deadline runs from the end of the statutory filing deadline for the accounting period in question.
In order to successfully submit your returns to both Companies House and HMRC, you will be required to provide the name of the individual who has formally signed off the Corporation Tax Return and Annual Accounts for submission.