Diagnostics in WebStation is a method of check the health of your system. Using Diagnostics you can also resolve several issues in the system, for example unconfigured trend log and forced values. You can check the following using diagnostics in WebStation:
Disabled alarms
Offline or invalid devices
Objects that require uploading or downloading to be synchronized with the current configuration
Forced values
Communication issues between servers
Unconfigured and stopped trendlogs
Time and time zone settings
Logged in users
Zoning issues