When trying to sign in to the merchant account in QuickBooks Point of Sale 2013, you see the error "BAD REQUEST."
There is a special character in your password.
Reset your password and create a new one that does not have a special character.
If this solution does not resolve the issue, you can read discussions and post messages and questions relating to your issue on the QuickBooks Point of Sale Community Forum. You can also review other available support options for additional guidance.