In the past I wrote application that connects to OneDrive using Microsoft Graph.
Now my boss asked me to write application to communicate with SharePoint, so the situation is like this: I have in a separate network (without internet connection) a shrepoint server. I can access to SharePoint management from browser like: http://mySharePoint:5186
my qustion, how do I register my application, since the sharepoint server and the application that will connect to this SharePoint are not connected to th internet. I mean how do I get client id, token etc..
I have tried to regitser the app i.w I wrote in browswer: http://mySharePoint/_layout/15/appreqnew.aspx
but I'm getting "Sorry, something went wrong" error at the browser