If your computer updated in January 2019 with updates KB4481480, KB4480970 and KB890830 then your remote access to file shares on other systems may be restricted. When attempting to connect you may get one of the following error:

An authentication error has occurred.
The Local Security Authority cannot be contacted
Remote computer xxx.xxx.xx.xxx ,this could be due to an expired password
Please update your password if it has expired for assistance contact your administrator or technical support.

Windows cannot access \\{computer name}\C$
Check the spelling of the name. Otherwise, there might be a problem with your network. To try to identify and resolve the problem, click Diagnose.

Handle is invalid

The issue is typically occurs if the user attempting to make the connection is an administrator on the machine that hosts the Share or if the share is setup with Everyone. If the user is "just" a user on the device that hosts the share, the connection may work fine.

A workaround has been published to address the issue. It modifies the Windows Registry and should be run on the system that hosts the share. Note that you need to run this from an elevated command prompt.
reg add HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\system /v LocalAccountTokenFilterPolicy /t REG_DWORD /d 1 /f

Reboot the PC after making the registry change.

The Registry entry defines how administrator credentials are applied for remote access. A value of 1 sets the restrictions to Audit mode.

Removal of the updates resolve the issue as well but will remove the security patches on the target system that Microsoft released in January 2019.

https://answers.microsoft.com/en-us/windows/forum/all/microsoft-updates-kb4481480-kb4480970-kb890830/831596f9-bb26-46f9-8b95-a2cc96bb3d72

Special thanks to George Gruel for the above post.

We hope that this information is helpful. Please let us know how this has helped you or if you have additional questions. As always Firestone Technical Resources, Inc. is here to help with your computer support issues - "Providing personal service for your impersonal technology."