Publish problem,need help

When I complete a program whit studio X,the program include send email.I run it with studio X,it is normal.But when I publish the program,and run it whih UI Assistant, it always failed, the message :
Something went wrong with .
Activity Send Email ( Send Mail X ) failed:

Directory “C:\Users\yy.nuget\packages\unicornname\1.0.4\lib\” doesn’t exist.

You can find the activity by searching id (press Ctrl + J to jumpt to activity):

I dont know what problem with it.

Hello, is your mail body a text or Html?
If html maybe the folder with template is missing inside the location provided in error. If it is missing please copy it from the uipath folder.