1. Quit Chrome completely
2. Delete the local state file.
For Mac
In a terminal window, enter the following:
admin@admins-Mac-mini ~ % cd Library/Application\ Support/Google/Chrome
admin@admins-Mac-mini Chrome % rm Local\ State
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For Windows
Go into Windows Explorer and make sure you can view hidden items.
Navigate to C:\users\(username)\AppData\Local\Google\Chrome\User Data
Delete the Local State file.