@Dhanasekar ok this is wat you can do (found on google )
0x800706d9 (office log in and sync/add - Microsoft Community
0x800706d9 (office log in and sync/add new microsoft account) & 0x80070426
Hi,
I was not able to log in Microsoft account in this computer (win10). I've tried several solutions:
Ran the windows store troubleshooter
Ran the windows Update troubleshooter
Windows firewall service disabled, re-enable it
Make sure that all three of these services are set to Automatic.
Windows Update (Windows Update to the latest version)
Storage Service
Windows defender Firewall
Windows update service enabled
windows fire wall turn off and try update again
Create a new user on the system and try from their account -> same issue
reset windows store
how to do windows reset
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