After opening Server Manager  it start collecting data, then I was getting an error and Roles nor Features will show. This is how I fixed this issue:

• Download the Microsoft System Update Readiness Tool from this link and run it.
• It might take a while to install but as long as you don’t get any errors just wait.
• Once completed, open the log file created at:
  C:\Windows\Logs\CBS\CheckSUR.log
• In my case, this is what I got from the log file:

• You can quickly realize there were 2 corrupted files. These are located at:
  C:\Windows\Servicing\Packages\
• Take ownership of these individual files and rename them to .OLD for example.
• Copy the same files from an updated Server 2008 R2.
• Test Server Manager and it should be working again, like it did for me.