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If USPS W2s are configured in ESS, on the grid, employees will have the ability to query their W2. Once a specific W2 is queried, you may either download 
a PDF version of it or view 
it on the screen. The employee will be able to see all W2’s generated for the employee in USPS--(ex: if an employee is to receive 2 or more W2’s in the same year all will be available in the ESS). The view option is also mobile friendly allowing users to view a W2 on a mobile device without having to download it
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first.
If W2s are configured, they will not appear in ESS until the district generates the W2 Archive Individual Forms in USPS (if the File Archive Module is enabled in USPS). Once scheduled, the W2 will appear in ESS.
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More Information on View/Print W2
Turning On/Off ability to view W2s in ESS
Users with Administrator Role have the option under System>Configuration>ESS Functionality Configuration to turn on/off View/Print W2 option.