if it solves without adaptive, that doesn't make much sense
what is your exact workflow?
what version/service pack are you working with?
probably worth posting your model
I have 2012/13 Education Version SP5.0.
My workflow is somewhat erratic. Don't think I can explain it. I have an assembly with 8 or so parts, I frequently adjust the geometry of the parts (occasionally making new parts) and re-simulate the assembly.
It's not too important, I think I should just move on as otherwise I'm wasting time.
knowing your workflow
looking at the files
both helpful in understanding what you're running into
sounds file specific to me, i'd probably clean it up and see if that helps, especially if adaptive works on other assemblies