I'm running IDM 4.02. My User App, which is currently used only for
password management, is running on a Windows 2008 R2 server. It has
been running without issue for years, but sometime between 5pm Friday
and 8apm Monday, it stopped. The server.log reports that the IDM.WAR
deployment fails. First it complained about "--" within a comment field
of the web.xml file (even though that "--" has been present since July
2014) so I removed the offending double hyphen. Now it is complaining
about 'invalid content' a few lines later in the same file.

Web.xml https://pastebin.com/2ft3Uvxu

server log: https://pastebin.com/z0D4X8Zc

I tried restoring the server from a weeks-old full backup, but that gave
the same result.

Suggestions appreciated.