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[Portal-URL]/admin/usersgroupmembership
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In some cases you may be locked out because of setting saved that do not allow you to sign in and change them. Please refer here to solve this:
For cloud - Portal user locked out - Unlock Site Security for a SaaS client
For skype: Unlocking Site Security from the database
Portal Logs location
To find the location of your logs please open log4net.config file in the portal configuration folder:
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