On Windows, go to control panel -> ODBC or control panel -> administration -> data sources, select the drivers tab, and scroll down to Easysoft ODBC-ODBC Bridge. The version is next to the driver name. In UNIX, look for the file /usr/local/easysoft/oob_install.info, scroll to the end of it and the last version installed should be present. Alternatively, you can run the demo program, select option 4 to test a connection, and the OOB client version is output.
If you are running the OOB Server HTTP administration interface simply browse http://myservermachine:8890 and the version is displayed at the top of the page. If you cannot do this, change directory to where the server is installed (on Windows, <SYSTEMROOT> and in UNIX /usr/local/easysoft/oob) and run "esoobserver version" or "./esoobserver version".
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