MailMessage out argument giving null value when it comes to Main from Process.xaml?

Hi All

I have a MailMessage argument in a workflow which is an out argument. In the workflow we are assigning it to a variable in Main.xaml. But when its coming to Main its becoming null.

Kindly help me understand why its becoming null ?

@Palaniyappan @lakshman

1 Like

hi @kkpatel

I think you are facing the same issue refer this thread

Change the datatype to Dictionary(OfString, MailMesage)

Hope this will help you



Are you getting any exception in that inner workflow ? Can you please run the process in Debug mode and check the values is Local panel.

Value in the inner workflow is good, no exception.

I think this one wont be feasible in my case. I just want to know why its coming as null in Main.


Check if you have mailmessages in both arguments and variable section. Some times if we unknowingly initialize both variable and arguments it will make argument as Null while coming out from the argument.

And also review if you have mailmessages argument is in correct direction β†’ Out.

Pls review and let us know. thanks.

No everything looks good. But still its coming as null.


Please check these criteria

  1. Name of argument and it’s variable is different
    That is argument name should be like this out_mailmessage and the variable name should be like mailmessage
    If they are same then it will confuse the bot and will throw error or null value at times

  2. Though you have the argument created in the involved workflow and also variable in Main xaml make sure you have imported them
    In invoke workflow file activity click on Import Arguments and check whether you have imported all arguments and also have passed the variable name as value to it
    Only then it will pass the value to that variable and we can use that in main xaml

Cheers @kkpatel