Random users having Authentication errors

Question

On our network we have random times to where many of our users cant log into their computers. User A has been using their computer for months, comes into work the next day and cant log into his own computer. (Credentials Cant Be Verified) Nothing has changed in his account, CAC card and network cable/drop is good. If we unplug the network cable (to skip network authentication) and then used cached info he can log in but is unable to access network drives to work. I can log into their computer with no issue.

User B is a brand new user and cant log in at all. (Credentials Cant be Verified) None of the tricks used to get User A into the computer work because there is no cached info for the new user. New User C is able to log in and authenticate and work just fine on their first login.

Its just weird how this happens sporadically between old and new users. User A may go days or even weeks with the same issue before it solves itself or they give up and use the VPN to log into the network. Its strange how the VPN authentication works fine but on the direct network they are unable to log in. Any help would be appreciated.

Answer 1

Hi. Thank you for your question and reaching out. I’d be more than happy to help you with your query.

There could be various reasons for authentication errors in Microsoft Windows. Some common causes include incorrect login credentials, issues with network connectivity, problems with the domain controller or Active Directory, or issues with the user's account in Active Directory. It's also possible that the problem is caused by a software bug or a malware infection. To troubleshoot the issue, it may be helpful to check the event logs on the affected machines and on the domain controller, and to check the status of network services such as DNS and DHCP. Additionally, it may be helpful to check for updates and patches for the operating system and any relevant network services.

If the reply was helpful, please don’t forget to upvote or accept as answer, thank you.

Answer 2

I'd check the security event logs on both ends for clues.

--please don't forget to upvote and Accept as answer if the reply is helpful--

Answer 3

No joy. Set everything as static and even made the user an administrator on the computer and he still cant log in. Credentials cant be verified.

Answer 4

I'd check the domain controller and problem members both use the static ip address of DC listed for DNS and no others such as router or public DNS.

--please don't forget to upvote and Accept as answer if the reply is helpful--