Problem: Create TIN dialog box crashes application if input data was browsed for and Map/Scene is empty
This problem is addressed in ArcGIS 8.1 Service Pack 1. See Related Information section to download this pack.
If you open the Create TIN From Features dialog from an empty Map or Scene that has no spatial reference, and browse for data as input that has a spatial reference, the application will crash.
This is a known issue.
Solution or Workaround
Add the data as a layer to the document before opening the dialog box.