Adding a sub-assembly to an assembly.

[Blessed4x]

I have a finished corridor, but now I need to add marked points to label a few key grade breaks in my cross sections.  When I attempt to add the marked points on some of my sub-assemblies it gives me the error that the sub-assembly is not part of the assembly.  I can right click the sub-assemly and choose "Add to Assembly" but when I rebuild the corridor it strips all the sub-assembly data from my assembly and leaves me with essentially a null assembly for the range (see the attached image).

This should be a simple procedure but once again the simple isn't what it seems.

[Blessed4x]

I don't really understand the error, the assemblies appear fine.  My cross sections are fine, the surface is fine.  How are some of the sub-assemblies NOT part of the appropriate assembly?  They seem to be.

[sboon]

If you open the Properties dialog for the assembly does it show all of your subassemblies in the Construction tab?

One other possibility - you might have accidentally copied a subassembly without moving it, so you have two of them stacked on top of each other.  One of the subs is attached to the assembly properly, but the one you're trying to attach to is not.

Steve
Please use the Accept as Solution or Kudo buttons when appropriate

[Blessed4x]

Thanks for your response.  I thought about the multiple sub thing, but there is only one sub.  Yes, they do show in the construction tab of the assembly properties box (see attached image)....one curious thing tho, is that when I select the suspect sub it will not allow me to move/copy/mirror it.  Those options are grayed out.  The sub in question is highlighted.

[Blessed4x]

I think I just found a fix.  Instead of labeling the Top of Curb since it would not let me add a marked point to the curb sub, I simply placed the marked point on the drive/ground sub that ties into the back of the curb.  It's the same point.  I don't know why I didn't think of it earlier.  I can only assume that somewhere along the line I messed something up in the assembly creation process for those few assemblies.  Oh well.  Thanks for your help, Steve.