I was trying to compare two Opensource Office applications: OpenOffice Portable 3.2.0 and LibreOffice Portable 3.3.3. If I open LibreOffice first, then OpenOffice does not have any problem on it. However, if I try to run OpenOffice fist then the LibreOffice Portable would give an error that another instance of the program is currently running. The "SinglePortableAppInstance" setting is disabled, so it should work properly. Can LibreOffice be used at multiple instances? Best regards.