Unwished duplicates and optimizing surfaces

[Uli Werner]

Sometimes (frankly said: often…) it happens an unexpected duplication of objects, even of complex objects with hundreds or thousends surfaces. I cannot see those duplicates, but I tried to eleminate them by using object – optimize surfaces. Unfortunately, that doesn`t work.
I make an easy test: I create a cube, duplicate the cube and then use object – optimize surfaces : The result is that there exist unchanged two cubes – one of them invisible for my eyes, but it blows up the file.
How can I fix that situation? – Thank for a hint!
Uli

[Tomkat]

The only way that I've found to be certain that you don't have duplicate items is...

UNCHECK "select through" items.
Set selection to "surface"
Manually select all visible surfaces.
HIDE them.

See if any duplicate items remain visible.

[Uli Werner]

Thanks for your suggestion - that is it: "MANUALLY".
As I use to crate one-faced surfaces, I must even check them fran both sides...
Uli