We help IT Professionals succeed at work.

wsus error: connection error - an error occurred trying to connect the wsus server

hello IT people

I'm facing this issue in my main wsus server. the main and only server for now.


so, what could be wrong?
Watch Question

Lead Technical Consultant
Basically the WSUSApplicationPool has a default builtin memory limit of 1.8gb.  If it exceeds that it will crash, taking down the whole WSUS Application.  The solution is go into advanced settings for that application pool and set the memory limit to 0.  That way it can use unlimited memory.

Option 1: Disable the firewall on the WSUS Server.

Option 2: Increase the amount of memory the WSUS pool uses, which was 1.75 GB by default. Increasing this value to 10-15 GB proved that WSUS works with no problem and the client devices start to report back and get updates. Make sure that you should have more than 16 GB RAM to perform this step if not, try to increase the memory size depending on the availability of your server memory.

Steps to increase the amount of virtual memory in WSUS pool
  • Open the IIS on the WSUS server and browse to Application Pools, Wsus Pool and right click & select Advanced Settings.
  • IIS Configuration for WSUS Server
  • On the new displayed window select Private Memory Limit (KB) and enter your new Memory Value, please note that the value to enter is in KB.
Ammar Bin YahyaVery Junior System Administrator


Ganesh Anand

I've  increased the memory size now to 15 GB

I'll see if it crush or not
Ammar Bin YahyaVery Junior System Administrator


I'm now facing the same issue, but in the replica server of wsus, i've done the same solution but it keeps crushing

any advice?
Ganesh AnandLead Technical Consultant

Do you mean that the second replica server of WSUS you are facing a similar issue? What is the error you are getting, how this replica server is configured upstream or clustered?
Ammar Bin YahyaVery Junior System Administrator


The main one that was facing the issue when i post the main question.
Now I'm trying to configure a replica wsus server to take the update from the main server, but I'm facing the same problem, you can check the same photo in the main question up there