Hi,
> When I have the MySQL data\joomla folder with FRM, IBD and other files,
> cannot the database be reconstructed from it?
This is not enough.
One of the most important files for rebuilding databases is the 'wamp\bin\mysql\mysql5.7.14\data\ibdata1' file. That's why I suggested you replace the entire data folder.
You can see the MySQL documentation that explains how to try to retrieve a database, but without any guarantee of success.
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