Can't select date in workflow using PWA

Question

I have a date field in my PWA Projects. I would like to use that date in a workflow to calculate another stage's due date. My thinking is to calculate a new date from the Project Data/Existing date field.

I am using Sharepoint Designer 2013, and when I try to calculate the new date, I add the calculate Action, and choose a value, select Project Data, and choose the Existing Date, but then OK grays out and I cannot use that value as part of the calculation.

Answer 1

The Do Calculate action is not used with date type

It's used with only numbers to can perform +, - ,/ ,*

Meanwhile, to be able to add days to a date field you should use Add Time to Date action as shown below.

Note: in Add Time to Date action specify the period that you need to add to your date and specify your Project Date field as shown below: