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After upgrading such a system, SPs that were receiving a Name Identifier in particular formats may end up receiving a transient format. This is a clear sign that the original V2 configuration was not correct. Cleaning this up ahead of time will prevent this problem from occurring.
This problem is particularly common in cases in which the "urn:oasis:names:tc:SAML:1.1:nameid-format:unspecified" Format was used. The only proper way to configure use of that Format in either V2 and V3 involves the use of the nameIDFormatPrecedence attribute in the relying-party.xml file, so if you don't see this in your configuration, an upgraded system will not produce that type of identifier when you expect it to.
The New Environment
Refer to the SystemRequirements page for details on supported software platforms. There are differences, so your existing system may well not support the new version.
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