fatal error when using mirror project command

[abeverlin369330]

I'm trying to mirror a project (file size 150MG) and have ungrouped all detail and model groups. Removed all cad and revit links. Only architecture in the file, no MEP or structure. It chugs for about 4 hours and then has a "serious error" where it allows me to save a recovery file, but when I do, the mirror command has not been completed. I have audited the file prior to opening. Any other things I can try to do to get this file to mirror? Revit 2013

[dannysmelcer564090]

I had this same problem. I made a copy of the project and slowly started deleting objects and performing mirror project to see what the culprit was. Eventually it came down to stairs drawn by component was causing revit to blow up. Try deleting your stairs and then perform mirror by project to positively identify it as the problem. Then you can cut them out, mirror project, bring them back in and manually mirror them or some type of workflow like this.