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It is generally safe to upgrade directly to the latest “newer” version as long as that’s only a single major version later than you start from. It is not required to upgrade to, for example, 5.0 before 5.1, etc. However, skipping does of course mean taking into account all of the accumulated ReleaseNotes covering all the intervening versions.
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This is unsupported; you must upgrade to the latest V4 release first. We do NOT support upgrades from V3 or earlier, primarily to eliminate extra compatibility logic in the installer and to minimize the problems that may arisereduce the variance of the starting point.
Upgrading from V4
The following are important prerequisites for ugrading from V4:
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