Connecting a subdomain for QR codes: the most common errors and how to fix them

You added the subdomain, set the DNS records and the dashboard still does not say “Active”? That happens often, and almost always a small mistake is behind it. One thing first: DNS changes sometimes take time. If you saved only a few minutes ago, wait before you change anything. How long that can take is covered in the article on DNS waiting times.

How to check your records yourself

You do not have to rely on the dashboard display. Replace qr.yourcompany.com with your subdomain and run these commands in a terminal (Mac, Linux):

• dig TXT _sameqr.qr.yourcompany.com +short shows the ownership proof. The answer must start with sameqr-nachweis=.
• dig CNAME qr.yourcompany.com +short shows where the subdomain points. You should see kunden.sameqr.com.
• dig A qr.yourcompany.com +short shows whether an old A record also exists.
• On Windows the same works with nslookup -type=TXT _sameqr.qr.yourcompany.com and nslookup -type=CNAME qr.yourcompany.com.

Without a terminal, an online DNS lookup does the job. Enter the name there, choose record type TXT or CNAME and compare the result with what the dashboard shows. It is best to query several locations, so you also see whether the change has arrived everywhere.

Mistake 1: TXT record at the wrong name

The most common one. Some interfaces add your domain automatically, others do not. If you enter the full name _sameqr.qr.yourcompany.com in a field that appends the domain itself, you end up with _sameqr.qr.yourcompany.com.yourcompany.com. A dig query finds nothing. The reverse also happens: you enter only _sameqr.qr, but the interface appends nothing. Look at your record list to see how the name is really displayed, and correct it. The value has to be right too: copy it completely, with no space at the start or end.

Mistake 2: main domain instead of subdomain

You always connect a subdomain such as qr.yourcompany.com, never the main domain yourcompany.com. If you created the CNAME for the main domain by accident, your website would stop working. Remove it and create it for the name qr instead. Also check that the dashboard shows the subdomain without a typo.

Mistake 3: an old record sits next to the CNAME

A CNAME must not exist alongside other records for the same name. If qr used to have an A record (or AAAA), many providers refuse the new CNAME, or the old record wins. If dig A qr.yourcompany.com +short returns an IP address you no longer need, delete that record and then set the CNAME.

Mistake 4: the Cloudflare proxy is on

If you use Cloudflare for your own DNS, the CNAME shows an orange cloud in the list. Then Cloudflare answers requests for you, and the service no longer sees the CNAME. Click the cloud until it is grey and says “DNS only”. A typical sign: dig returns IP addresses instead of kunden.sameqr.com.

Mistake 5: typo in the target

Check the target letter by letter: kunden.sameqr.com. Common slips are a missing dot, a doubled “com”, a leading https:// or a slash at the end. A CNAME target is just a name, not a web address.

Mistake 6: the certificate is not ready yet

If both records are right but the status still says “Being set up”, the HTTPS certificate is being issued right now. That usually takes only a few minutes. Open the code on your phone only once it says “Active”. If the status stays stuck for a long time, the “Own domain” window in Same-QR shows the message.

If everything looks right and it still fails

• Do not delete anything at first. Check that both records are visible with dig.
• If you saved only just now, wait and check again afterwards.
• Click “Check” in the dashboard again once the records are visible.
• Write to support with the result of your dig queries, which saves follow-up questions.

Frequently asked questions