Error During TFS Search Configuration

If you're experiencing "VS403185: An unknown error has occurred during Search configuration" error when configuring search using TFS configuration wizard, then most likely you have attempted to configure search to run using a domain account. At this point, when using TFS Configuration wizard, search can only be configured to run as to run as NT AUTHORITY\NETWORK SERVICE. So, change the search service account to NT AUTHORITY\NETWORK SERVICE and things should go back to normal.

Obviously, you can still configure search in TFS 2018 with custom credentials for Elastic Search. You just need to configure search separately from application tier configuration. So, uncheck the Search configuration checkbox option in the TFS Configuration wizard and proceed. Once the TFS is configured, go to the Search tab and proceed with its configuration using custom credentials.