When I try to look up for people and/or groups from Active Directory, an error with a red font color shows saying “Sorry, we’re having trouble reaching the server.“
To fix this, you must have an access to the Central Administration site.
- Go to Application Management > Web Applications > Configure alternate access mappings.
- Click Add Internal URLs.
- Choose a web application where you want to apply the setting from the Alternate Access Mapping Collection button.
- Type a valid URL protocol, host and port. For example, http://192.168.0.21. In my case, this is the IP address of my Active Directory, where my users and groups are pulled from.
- Click Save.
- Optional: Restart the web application from the IIS Manager, if you cannot wait for it to take effect.
- The error should be gone by now, if done correctly.