Hello, I can open most Architect's .dwg drawings, but on occasion I can see the entire drawing in preview, but then only a few small blocks will appear. Why does this happen? I appreciate any help I can get. Thanks!

This could happen for couple things:
1. Some layers coul be off
2. Have to load Xref. (I think this is it), Insert-Xref Manager-Attach-OK
Hopefully it will help.
Ferna

Thank you!