If one version of your address shows a certificate warning, such as NET::ERR_CERT_COMMON_NAME_INVALID, the certificate does not include that name or that name points to a different server.
Overview
A certificate is issued for specific names. A certificate for www.yourdomain.co.tz does not cover yourdomain.co.tz unless it was issued for both. The browser warns when the name you typed is not on the certificate.
Why it happens
- The root domain still points to an old server that has a different certificate or none.
- The platform issued a certificate for only one of the two names.
- Your device still has the old address cached.
What it means
Your DNS or certificate is only partly set up. When both names point to the same service and that service issues a certificate for both, the warning goes away.
How to fix it
- Check both names have the right record: see www works but the root domain does not.
- Remove old A records on the root domain that point to a previous server.
- In your platform, make sure both names are added and HTTPS is switched on for both. Renew the certificate if needed.
- Wait for the certificate to be issued, which can take a short while after the records are correct.
- Clear cache or test on another network. For cPanel hosting, run AutoSSL: install a free SSL certificate.
Still need help? Get support
Open a support ticket
A ticket is the best way to get this fixed: it keeps your details, and we reply in the ticket.
Prefer to talk? Call 0758 309 999 (fastest line). If that line is busy, call 0753 930 000 (longer wait).
Related articles
- Website Works on www but Not Without It (or the Other Way Round)
- Domain Shows a Parked Page or "IP Address Changed" Message
- Connect a SakuraHost Domain to Netlify (A and CNAME Records)
- How to Fix "Your Connection is Not Private" SSL Errors
- How to Install a Free SSL Certificate on SakuraHost (AutoSSL)
Frequently asked questions
Is the warning dangerous?
It means the connection is not verified for that name. Do not enter passwords or payment details on a page with a certificate warning.
How long until HTTPS works?
Often within minutes after DNS is correct, sometimes an hour or more.
Written by Jumbe Nylon, Founder & CTO, SakuraHost. Updated October 2026.