When going into the environment category it appears blank and you will get the following message:
"No data to be set"
If you have a look at the logs you see an error that points to the K2 Management service instance failing to execute and also:
"Object Reference Not Set to an Instance of an Object"
Go to the SmartObject tester tool which can be found within the following directory:
Program Files (x86) > K2 Blackpearl > Bin > SmartObject Tester
Search for the following: "SmartObject Environment.Permission" and execute the list method.You will need the environments ID which can be grabbed from the environment.environment table in the K2 DB.
Afterwards, if you see any users being listed here, please remove them by setting "executing the update method" and nullify their options. After this clear the cache and go back into the management page and you should be able to see the environment fields once again.