Note: This article has the reference to the issues with the fixes available:
- #PPPM-3170 "Adding DNS TXT records longer than 255 characters resulted in inability to start the DNS service."
- #PPPM-8655 "TXT records longer than 255 characters can now be added."
Unable to add TXT DNS records longer than 255 characters in Plesk for Windows even if semicolons are used to split it record in blocks and bypass this issue.
DNS server does not serve requests to a domain with DKIM record longer than 255 characters.
SPF record not recognized when it is longer than 255 characters.
Plesk for Windows: bug #PPPM-8655 which is fixed in Plesk Onyx 17.8.11 Update 51
Plesk for Linux: bug #PPPM-3170 which is fixed in Plesk Onyx 17.5.3 Update 13
In Plesk for Windows, upgrade Plesk to Plesk Onyx 17.8.
In Plesk for Linux, upgrade Plesk to 17.5 or higher.