Support

Troubleshooting

Decode gateway rejections, pending states, and “why didn’t this land?” moments.

• Fixing common CT600 submission errors

  Authentication failures, invalid UTR, period conflicts, and business-logic rejections explained in plain language.

• Why a filing shows as pending with HMRC

  What “pending” means after submit, how long to wait, and when to open a support ticket.

• HMRC authentication failure on CT600

  Five usual causes — wrong credentials, CT not enrolled, expired session, mismatched UTR, or environment mix-up.