Using SW19 trying to open any assembly file, saved on local or on network, will result in SW opening and viewing the file but me not able to see anything in the part tree or the ribbons on top. Everything is greyed out. I can see the actual assembly and rotate it just fine, it's not even slow or jerky at all. I am only able to open an assembly if I have already opened every single part and sub assembly referenced within the larger assembly. It's not such a big deal for small asm files, but we have assemblies with hundreds of parts in them. I would be here all week just trying to open each part before I could get any work done. Any suggestions?