I'm unable with ADFS to Synchronize with SharePoint on Premise (2016). If I use the 2013 Groove it seems to work fine but with 2016 I'm unable to Synchronize.
Not sure if this is a SharePoint wide issue but if I open Excel or try and sync with OD4B I'm getting a Windows Security Prompt that leads to me unable to connect etc..
The Site is through a WAP but on or off VPN it doesn't work, the site is in my trusted list and i've set to use current username and password to login. The fact I'm getting a Windows Security Prompt makes me think this isn't working properly. I am able to open the Document Libary with File Explorer, but wtih nothing else.
I'm using Email and UPN with Claim and I have setup User Profile Service.
I notice in Fiddler when Groove is connecting to the site i get a 401 unauthorized, but can't work out why its not using the login with IE for the Sync client.