We've seen an issue with partners who have upgraded to Sage 50c 2019 where a watermark.xml file located within the root of the Sage company data does not have its version updated correctly by Sage during the upgrade process.
Please confirm that the watermark.xml located within the Company Data path matches what is listed for the Company Data version. (See image below.) If the contents of the watermark.xml do not match the Data version, then setting it to match should resolve the issue.
