***SOLVED*** with this link, more explanation in the comments
https://confluence.atlassian.com/jirakb/service-desk-installed-but-not-enabled-found-dependent-enabled-plugins-for-plugin-800703376.html?_ga=2.205787987.1335306900.1529910575-1588952890.1515060119
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We started implementing Jira a few months ago, we installed Jira Software and Jira Service Desk. Since we were not using it we deleted the workflows and permissions of the Service Desk (yes bad choice indeed, let's skip that!).
Now we want to start using Service Desk, in the Applications Manager we see:
"Jira Service Desk is licensed but not currently installed. INSTALL"
Also uploading from the "Upload an application".
So that Install obviously doesn't work... It says "An unexpected error occurred. Refer to the logs for more information."
So I tried downloading the files to my server and executing them, so with the Service Desk installer, I used the Upgrade over my Jira Software installation and everything said: "Yeees you made it, you installed it!" and when Jira was up again, it had the same:
"Jira Service Desk is licensed but not currently installed. INSTALL"
My logs are uploaded to https://ufile.io/rglvz since every time I try to upload them here (as any kind of text) I get that they have invalid HTML ( ?!?!?!?!?! )
I'm guessing that has something to do with the fact that we deleted all the workflows, permissions and screens from the Service Desk Projects but there must be a way to put them back as default, without losing all the other configuration of our Jira server, RIGHT?!
Thanks in advance! Sorry for all the edits! 