Nested models are not visible

[dinushki.n]

Nested models are not loading error is appearing.

Tried changing the reference type but seems to have no luck.

[alan.johnson7YLND]

Could you provide a bit more information to your problem?

[dinushki.n]

in my master plan there are 13other linked models. 

Master Plan model- A

Spa-B

Nested models in spa- C1 and C2.

C1 and C2 is linked to B as attachments.

B is linked to A as overlay.

C1 and C2 not visible in A model.

get the following error message.