Encountering error 401 1 2148074254 while accessing the webservice from webserver in NLB environment

Hello,

I have an ASP.Net web application hosted in NLB infrastructure with 2 web servers and 2 app servers. I have 3 web services running in the application server with windows authentication enabled. Other settings as follows

1. Anonymous authentication is disabled
2. Basic authentication is disabled
3. Digest authentication is disabled
4. ASP.NET Impersonation is disabled.
5. Windows authentication is enabled
6. Negotiate is on priority with both Negotiate, NTLM is enabled.
7. using custom identity: DOmain\User1
8. useAppPoolCredentials set to true
9. useKernelMode set to False

As per my observation, user encounter error 401 1 2148074254 when website access a specific webservice(let's say webservice 1). When a user accesses the same function again then there is no recurrence of 401 error.

Noticed the Start Mode was set to “On Demand” mode in app pool settings. Tried changing the Start Mode to “Always Running” and Idle Time-Out to “0” but still encountered the same error and the same pattern.

Regards,

VHK