Appstore has limited function and iTunes fails to open after High Sierra upgrade

Appstore has limited function and iTunes fails to open after High Sierra upgrade

State Number Two (current set-up)

iMac upgraded to High Sierra version: 10.13.1

iMac (27-inch, Mid 2011) Memory 16 GB 1333 MHz Core i7 S/N:D2***HJW

Problem 1: Appstore loses function

1A “Updates” and “install new app” freezes (beachball)

1B “Purchased” tab allows opening of “purchased apps”

however the top line “You have 1 app to accept...”

the “Accept” button freezes (beachball)

1C Quick Links to “welcome”, “account”, “redeem” and “support” are unresponsive.

1D Appstore preferences fields: “Checking if automatic...downloads...enabled” and

“Password Settings” Freeze (rotating fan)

Problem 2: iTunes (12.6.2) freezes

2A Opening page freezes (beachball) on opening.

State Number One (former set up)

IMac at OS macOS Sierra 10.12.1

iMac (27-inch, Mid 2011) Memory 16 GB 1333 MHz Core i7 S/N:D2****HJW

[Note: itunes worked at this OS revision]

3A Unable to upgrade mac OS Sierra 10.12.1 to 10.12.6 or

3B Unable to upgrade iTunes (from 12.6.2 to 12.7) via Appstore automatic upgrades

Despite daily invitations to upgrade both 3A and 3B, instals both failed numerous times.

3A failed “An error has occurred..permission denied (13)” or

“Some updates need to finish downloading before they are installed.

Your computer will restart to complete the update”

3B Ultimately got stuck trying to calibrate download. So I gave up and waited for the next big release (see above)

Details macOS Sierra version: 10.12.1 iMac (27-inch, Mid 2011)

Memory 16 GB 1333 MHz Core i7 Serial Number D2*****HJW

I have done several things to solve these problems, need more focused expertise.

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