Hello,

I've recently run into a problem regarding mates.

We have a large assembly with 10+ sub-assemblies (with hundreds of parts total as various sub-levels), all mated together and fully constrained with no mating errors, and today I opened it up to add another sub-assembly, added the 3 related mates, saved, and closed...

A co-worker later opened up the assembly to view and we found the assembly mates had completely vanished, the mate "group" is still visable but it is empty, all sub-assemblies have remained constrained as well (can't drag and drop them),

no additional forced mates can be placed... but I can create duplicate mates (like creating a parallel mate that doesn't affect current position) that cause the related sub-assembly to become unconstrained (over-rides what solidworks has retained as it's correct position) and utilizes only the newly made mate for position and the sub-assembly can be moved via mouse drag and drop

I've tried right clicking sub-assemblies to "view mates" but just an empty box pops up

There is only the default configuration available in the assembly, no additionals have been created

FYI assembly & sub-assemblies were created in 2012 solidworks, no conversions were present

any other information would be greatly appreciated

thanks in advance,

- Jeff