I have been having this issue for weeks now. Almost every time I try to edit or create an alert, the page resets back to the alert list with a note at the top, "A draft alert was saved at", with the links to return to editing or delete. If I try to edit the draft, it comes up with a blank form. I have been on NPM 12.2, with most of the modules installed, for at least 6 months. This problem recently started to occur, first noticed June 8.
I have 1 windows 2016 APE, 1 2012R2 Primery, 3 2012 R2 APEs, 1 2016 NTA database, 1 2012 R2 AWS, 1 2016 SQL Server with 2016 MSSQL installed. Total of 8 servers.
My list of troubleshooting steps is extensive.
Rebooted the entire environment (three times AND prayed)
I have upgraded all .NET framework version to 4.7.02558, across all servers.
Deleted subscriptions notifications etc.
Checked server event logs, nothing correlates to the times of occurrence
Copied all IIS settings from test environments that worked correctly
There does NOT appear to be any database connection issues, SQL server is on the same subnet as the primary
Error occurs on both primary and additional web server, even when accesses web page by IP
Servers are not load balanced
I did have the webpage error caused by windows updates, I had to remove an update from one of the servers to edit nodes on the 2016 APE
I have added and removed HTTPS functionality from the website
Turned out to be issues with our proxy server.