Can't access server from Windows client after password change

Hi everybody!

My problem is that I can't access my ownCloud for syncing after I have changed my admin password. I am trying to access my admin's account which I am using usually.

I am getting an error message: "Access forbidden by server."

This problem first occured after I changed the password of the admin's account.

This is what my error message looks like from trying to access the webdav from my browser:

OCA\DAV\Connector\Sabre\Exception\PasswordLoginForbidden password login forbidden

This is the error log in my admin panel:

opendir(/tmp): failed to open dir: Permission denied at
/www/htdocs/accountdir/cloud.myowncloudserver.de/lib/private/TempManager.php#188

I am using server sided encryption and have not yet created a recovery key (if this might be a problem on the access). I am also using Wurst's new TOTP module for 2FA.

I have created a new user on the same ownCloud installation which can be setup on the client perfectly and connects. I am also still connected via my phone and the Android ownCloud app with the admin account. I am still able to get into my admin panel with my browser.

How can I access my ownCloud account with my admin user again??

Thanks for helping.

ownCloud v.9.1

You wrote that you're using 2FA, probably you should activate "App passwords" for your sync-clients (just an example):

**edit: and, if you're having access to its shell (SSH) and able to run occ-commands, try the following:

sudo -u www-data php occ user:resetpassword user123

but do not forget the already changed passwords due to encryption recovery. (be vary careful with that)