Hi,
Yes you can use Windows 2019 to install your new adconnect server.
For your information ,Windows 2022 is not yet support.
If you want migrate adconnect server from windows 2008 R2 to new server you should perform the following steps:
- Export adconnect configuration from old server
- Export custom rules from old server
- Install and configure new adconect server and put it on staging mode
- Enable staging mode on old server
- Disable staging mode on new server
- uninstall adconnect on old server
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