Hello,
Only E0703 was affected by that issue with jmx.password, so that can't be it. Recently I've seen a few situations on different versions where it seems that iMC tried to update the iMC\client\conf\server.xml file, but after failing to do so (for example due to the user uploading an invalid HTTPS certificate file on the web interface), the file gets blanked out, and this causes jserver to fail on startup.
Can you please check if that file is blank or not?
If it's blank, you can find an original to replace it with in iMC\deploy\components\iMC-PLAT\V700R001B06D027\client\client.zip (the V700R001B06D027 text would be referring to the E0705 version - you could also find it in one of the newer/older version folders). Open that client.zip archive and under client\conf you can find server.xml. Restart iMC afterwards and jserver should now start.
Note that if you use your own HTTPS Certificate, you should manually edit the server.xml file and replace the path to the keystore and keystore password as needed (keystoreFile=, KeystorePath=) in there before you restart iMC.