What should I have in mind when upgrading / updating WHMCS?
Each time you update your WHMCS, incremental or full update, check if the clientareadomaindetails.tpl file has been overwritten. In such case you need to add again the required modifications:
Template file clientareadomaindetails.tpl
If no changes have been made by whmcs, re-upload the clientareadomaindetails.tpl file from your previous version. Otherwise, you need to add the necessary modifications as per the installation documentation for RAMDI, REMDI and RAMEI:Howto install R.A.M.Dns Interface V3 => TAB Step 2
Howto install R.A.M.Email Interface V3 => TAB Step 2
Howto install R.E.M.Domain Interface V3 => TAB Step 2