Since yesterday I\'ve been getting the following error when trying run an app on my device: \"A valid provisioning profile for this executable was not found.\". This is afte
I was struggling with the same issue and the solution in my case was to log in to the developer account(s). After updating to Xcode 10 all accounts were logged out.
Use the menu "Xcode -> Preferences ... -> Accounts" and make sure all accounts you use are logged in so the provisioning profiles are accessible.