Hmm..hope everyone has tried using CRM 2015 SP1. The Navigation tweaks are pretty awesome so kudos to Microsoft Dynamics Team for working on the navigation tweaks!

So what’s the exact problem?
I haven’t tried the CRM Outlook plugin for years, so I had to do a bit of research to solve this issue..
Tried searching the internet didnt give me any useful results…this made me think for a while because if this was an issue, many of them would have raised questions in community portals or blogs..
I even tried installing and uninstalling Outlook, still there wasn’t any luck! it.
Finally, I ended up in Outlook Settings, I then clicked on view… Customize Reading Pane, Ohhhh wait! What does that do now?
I went ahead and clicked on it..
TADAAAAA!
The data which was being shown was the Reading Pane and the data it shows are not customizable (except you can remove some sections if you want).
What is CRM Outlook Reading Pane?
The reading pane is a quick way to view contact information in a read only view. It’s useful Microsoft have provided some quick view functionality, frustrating you can’t edit it and puzzling I couldn’t figure out where this information was coming from.
If you think of the CRM reading pane working like the normal Outlook reading pane, which shows you some details about an email without you having to open/read the email.
The CRM reading pane works in a similar way, showing you some details about the contain without having to open the contact record. This works OK except when you have customized the contact record significantly because the new fields won’t be shown in the reading pane and fields you have removed from the form will be displayed
References:-
Customize the Reading Pane in CRM for Outlook
Navigating the CRM Outlook Client
How to Hide Tabs in Reading Pane for Dynamics CRM Outlook Client