Exchange Toolbox Snap-in Unavailable

 Sometimes when running Exchange Toolbox I'll get a Snap-in Unavailable message. Specifically:

This snap-in performed a non-valid operation and has been unloaded. To continue working with this snap-in, restart MMC or try load the snap-in again.

Exception Type: System.Runtime.Serialization.SerializationException

Exception Message: Type is not resolved for member.

The problem usually has to do with IIS. Open IIS Manager, expand the 'Sites' folder in the left menu. In the right Actions pane, select 'Bindings...'. The bindings have to be like this screenshot (via Spiceworks), specifically the binding needs to include HTTP to all assigned IPs at port 80 and HTTPS at port 443.

If that is already set, a restart of IIS has helped.

Office error 0xc0000142 (updating, please wait)

 I've run into Office 2016 failing to launch where a windows shows up which says "Updating, please wait", followed by the application (Excel, Word, etc) crashing with the above error.

The solution is to restart the 'ClickToRunSvc' service in Task Manager (under the services tab).

WS-Management service cannot process the request

WS-Management service cannot process the request

In Windows Server, launching PowerShell can sometimes result in an error where the shell can't connect to 'remote server server.contesso.local', even if this is the local computer the shell was launched on. The error message is 'The WS-Management service cannot process the request. The load quota for the system has been exceded'.

The solution is to:

Logon to the specfic Exchange server on the error message.

Open IIS Management Console and navigate to IIS Application Pools.

Restart PowerShell App Pools. 

The cause, via Solarwinds:

This issue is the result of the IIS/Powershell App Pool being overloaded. A restart of it will reset the App Pool back to zeros.  If the server is still having issues, you might see that the system load ends up maxing out again, which can cause issues with polling. Investigation into the load on the server is recommended.