I have an ASP.NET web API deployed in IIS on a windows server.
One client is reporting they cannot connect to this API through our .NET application. They are getting the following error message:
A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond
I have been browsing some other posts where the same error has been reported, but I'm still not finding any way forward...
- There are other clients using the same application where this is working fine, it is only this one client reporting these issues.
- They claim they can access the API endpoints using their browser on the client machine, it is just not working through the application.
I thought at first the problem would be related to the firewall blocking the requests. But can the firewall block requests that are made through a .NET application, yet allow them in the browser? In that case which firewall settings should be looked over?
Since the problem only occurs in the .NET application, is there some code changes that could possibly solve this? But in that case, how come it works for other clients?
- Where is the problem most likely located? Server? Client application? Client environment (firewall)?
- How do I best find the real cause to this issue? I have full access to the server but unfortunately not to the client having issues.
I understand it may be difficult to give a definite answer to this, but anything that could lead me in the right direction would be extremely appreciated.