On Locator Control Manager, click on Web Users section, and find the Client (Company name):
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Find the webuser and click on View/Edit (or View) and login to the webuser;
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Click on drop-down box next to account name and select Account settings;
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Click on Change password, fill in the fields and press on change password;
​Note: you need to know the webuser's old password. Otherwise, use password recovery via verified email address.
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