Click the 'Programs' option from the main menu within Powersuite. Select 'List Editor'.
In List Editor click the plus next to 'billing' Select the entry 'Product codes' Double click the 'Vat Percentage' column to edit the VAT
Todays Clear Code:
61936
To use the clear code enter "CLEAR" as your User ID and the clear code as the password.
This should clear all users allowing you to log back in as normal.