SCCM - Issues with updates 0x80244022

[Explorer]

Having some strange problems with Windows Updates on SCCM 1806. This is a recently installed system so it's something which has been present since setting this up.

 

Whenever I click check for updates from a client PC I am getting the error 0x80244022.I've taken the following steps so far:

 

Check that WsusPool is running - it is.

Increased the maximum memory for the WsusPool

Run the server cleanup wizard from the WSUS console

Local group policy shows the correct WSUS server

Doesn't appear to be a DNS issue as I can see the SCCM server from the client and the client from the SCCM server

 

Here is the same error in the WUAHandler log: