Hi Sarah - while Daniel continues to investigate this - are you comfortable with editing a record in a database table? There is a PostgreSQL utility you can use to access the repository, access the table and manually set the flag to enable HTTP - which will use port 80 as well. If you do this - you should be able to access the QMC providing port 80 is not in use. The you can use the QMC to make the port change. If that is also the case - we can find the table that has the proxy port record and make that change manually.
Let us know if this is an option you wish to pursue.
We have seen this some times when the Port is blocked and best is to deactivate this Software at least to change the Port in the QMC or change to http. It is possible to do this in the Database directly, but would recommend to use the QMC. Make sure to use the changed Port afterwards in the URL or http depending on the change. Not sure, but I think this could be on the list to make it possible to change durring installation.
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