Trying to understand and resolve very slow account logins

I am trying to figure out and resolve why several accounts on my Dell XPS Windows10 Home system take upwards of 5 minutes to login. This is a stand-alone system; there is no Domain. The Administrator account and two of the regular accounts require 5 minutes to pass - during which there is nothing displayed but a blank black screen - before the desktop comes up. One of the standard accounts is a local account and the other is tied to a Microsoft account. However for the fourth account (a local standard user account), the login process is without any such delay; a login passes driectly to showing the desktop without any problem whatsoever.

The Windows 10 is regularly patched and has Norton Security for its A/V. It is not in a Domain.

Once logged into each acount in turn, I have brought up the 'Task Manager' -> 'Startup' listing. I see each login has the exact same listing of login apps as the others. For each login account, the listing of startup apps has the same "Disabled" or "Enabled" (for examle: 'Skype' is listed for each account and in all cases it is "Disabled") . The key difference is that "Not measured" is given as the 'Startup impact' for all of the accounts except for the one that logs in without the 5 minute delay. The one account (which is a standard account, not an admin account), shows "High" , "Medium" and "Low" for each of its startup tasks.

I have run, as the admin, "dism /Online /Cleanup-Image /CheckHealth" and have used "sfc /scannow" and have done "chkdsk c:" . All report no problem.

This morning I created a fifth account, another local standard account. My intent was to simply abandon one of the troubled local accounts by simply moving all its files over to this new account. However this new account immediately has the same issue; every login requires the 5 minute blank black display before the desktop is displayed.

What should I try next?

I should add a couple of things.

1st: The troubled accounts have exited for over a year. The problem began about two months ago. So for the better part of a year this slow login issue did not exist.

2nd: During the 5 minute blank black screen period, CTRL-ALT-DEL works and allows Task Manager to be started for the account which has been started. Task Manager functions and shows normal CPU and Disk and network activity. I am not sure how this can be used to help diagnose what is wrong.

Welcome to the forum. Does the MS account login to other pcs I am thinking its down loading the profile as its syncs MS accounts

Hi. I manage 50 PCs of varying ages all with Win 10. I quite often see this problem on random PCs. I've now put it down to Win 10 bugs which hopefully one day will be fixed, but I'm not hopeful.