Hi Marco,
Further to above suggestions:
Your log file shows the first ERROR is after the reading of the APMEnterpriseManager.properties file:
8/16/18 03:02:23.311 PM CEST [INFO] [main] [com.ca.wily.jasypt.APMEncryptablePropertyPlaceholderConfigurer] Loading properties file from URL [file:C:/Program Files/CA APM/Introscope10.7.0.45/./config/APMEnterpriseManager.properties]
8/16/18 03:02:24.436 PM CEST [ERROR] [main] [Manager.AppMapSubsystem] APM Data model subsystem is unavailable so AppMap feature is not functional. Please check the DataBase connectivity or disable AppMap feature.
At that stage the tess-db-cfg.xml file is also read to connect to the APM DB. Can you please reset that file to use the plaintext password for the APM DB user i.e.
<property name="hibernate.connection.password">plaintext_password</property>
<property name="plainTextPasswords">true</property>
If that does not resolve the problem on next restart please try to clear the EM cache per this KB: How to clear the Introscope OSGI cache? - CA Knowledge
Then before restarting the EM also enable DEBUG in the IntroscopeEnterpriseManager.properties file i.e.
change: log4j.logger.Manager=INFO,console,logfile
to: log4j.logger.Manager=DEBUG,console,logfile
We can then have a look at the new log file if the problem still persists.
Also as you mentioned a previous permissions problem if you are running the EM using Introscope_Enterprise_Manager.exe directly (not as a Windows Service) try to execute it with "Run as administrator" option.
Hope it helps.
Regards,
Lynn