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This section describes how to upgrade your existing eZ Publish 5.1 2 installation to version 5.23. Make sure that you have a working backup of the site before you do the actual upgrade, and make sure that the installation you are performing the upgrade on is offline.
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If you are using custom extensions, the sub-directories inside the "extension" directory will also have to be copied from the existing 5.1 installation 2 installation into "/<ezp5-root>/ezpublish_legacy/extension/". However, make sure that you do not overwrite any extensions that are included in eZ Publish distribution, which currently are (Note: As of eZ Publish 5.2, these extensions have the same version number as eZ Publish):
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