Product(s):	AECOsim Building Designer
	Version(s):	08.11.09.866
	Environment:	N\A
	Area:	General
	Subarea:	N\A

Problem Description

Unable to select some elements in the 3D model, what could be the problem?

Steps to Resolve

This could be due to bad data, First try choosing File > Compress to clear any unnecessary data in the file. Sometimes that's all it needs to resolve this type of issue(s),  if that doesn't work try the following:

1- Create a new file and reference the "bad" file into the new file, copy all of the elements from the reference attachment into the active DGN file, and then detach that reference.

2 - Select all the elements in the file and apply the Key-in TFREBUILD.  This may also help generate the elements and strip them of any bad data.

As a good practice always back up your files to prevent loss of data.