I have sent a message about this, but posting here too in the hope that other users may have experienced this and can help if the helpdesk take a while to look at it.
I have installed Milksync today and the following happened:
1. Online account (web based) now shows all tasks, whether created on iPhone or Outlook
2. iPhone is unchanged, no Outlook tasks have been added to it despite them making it to the web account, but tasks created in the app are still there
3. Outlook - literally every single task has been deleted. The list is empty.
2-way syncing and "all lists" are enabled.
Any advice? :-(
Posted at 2:15pm on March 26, 2013