Okay here goes,
I'm encountering a problem when I exit an assembly without saving. I'll try to paint the full picture first.
I have a large assembly with several assemblies within the large or main assembly. If I open one of the smaller assemblies in order to inspect something and then decide it doesn't need any changes I will close that assembly without saving in order to get back to my main assembly.
Now, this doesn't happen every time, but sometimes when I close this assembly I receive one or multiple error messages saying "It is not possible to replace the component because it is currently open in a different window (could be a separate window or an assembly window that references the component)" When I get back to the main assembly some parts are suppressed.
I think it could be that these parts are located in common folders we use for shared parts. This way we don't have to copy a part into every single folder where it will be used. I think this is pretty common practice.
I could save the assembly every time, but this shouldn't be necessary, especially when I've made irreversible changes.
Please let me know if you need more information. If anyone has any idea what's going on or how to fix it I would appreciate any feedback.