If not explicitly specified at JVM start-up, then the Java/JVM process for the Enterprise Manager will use the current Windows OS time zone. However, it is possible for the time zone to appear correct on the Windows OS but for Java to still not read it correctly due to the relevant Windows registry settings being incomplete. In that case the JVM defaults to VET (Venezuelan Standard Time) because VET is the null time zone for Java.
To resolve the problem change the Windows OS time zone to a new value, save, change it back to the required time zone and save again. This will ensure that the time zone registry entries get correctly updated in the windows registry.
Alternative workarounds are to explicitly set the JVM time zone as an additional parameter in either the IntroscopeEnterpriseManager.lax file (starting EM from command line) or the EMService.conf file (starting EM as a Windows service) i.e. IntroscopeEnterpriseManager.lax file:
Add "-Duser.timezone=xxxxx" to the end of the existing property "lax.nl.java.option.additional" EMService.conf file: Add an additional wrapper property e.g. "wrapper.java.additional.10=-Duser.timezone=xxxxx"