Unable to process invalid item

When i use BEND to connect item in slope pipe, In command line always appear
Unable to process invalid item  
or Catalogue error for componet BEND 1 of....
catalogue parameter number (4) out of range.
Anybody can help me!

You should go to Paragon and check the model category for the Parameter 4.
Probably it is not defined or you only have Parameter 1, 2 and 3.