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Because the installation uses exactly the same process as a manual install sequence, from V5 onwards it is quite safe to intermix “manual” upgrades and MSI-based upgrades. Of course, the version displayed by the “Programs and Features” settings will display the last MSI version installed. Always use the Status command or web service to display the current IdP version when in doubt, or check the log at startup.
When upgrading from V4, when the previous version is uninstalled this will include any bundled jetty-base. If you are not deploying your own servlet container, then you will need to install the jetty-base Installer as well, do this after you update the the IdP from V4 to V5 (since this update will remove the old jetty).
After an IdP update, you will need to stop and restart the web server you are using (and as always, it’s best to stop the container prior to any updates).
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