If you are trying to connect to, make sure you are providing (or whatever is appropriate!) but not in SharePoint Online.

When you are working with multiple tenants, make sure the supplied credentials are matching the given URL.Your account may be MFA (Multi-factor authentication) enabled! If yes, either MFA must be turned OFF or you have to follow the methods described in How to Connect to SharePoint Online with MFA-enabled accounts from PowerShell?.

Your saved password in the Windows credentials store could be incorrect or expired (especially when you use PnP PowerShell module Connect-PnPOnline to get credentials from the Windows Credentials store).

Your password may be expired, or your account may be locked out or disabled.

Check if you are able to log in using a web browser with the user name and password given in the PowerShell script.

Your user name or password could be wrong (Obviously!).

Here are the possible causes and solutions: This could happen in any PowerShell method like CSOM, SharePoint Online Management Shell Connect-SPOService, or PnP PowerShell Connect-PnPOnline cmdlet. I’ve experienced this error in SharePoint Online PowerShell scripts a couple of times. Problem: Getting “The sign-in name or password does not match one in the Microsoft account system” Error in SharePoint Online.

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