HFSS.lock HFSS.auto

Every time I open my project file, two new files (HFSS.lock and HFSS.auto) are created. Can anyone suggest how to cope with these so that they may not create automatically?

I copied this design in another folder and then copied back in the previous folder.
I have doubt also that due to these files it happened: I tried to run "interpolating" simulation but it took much more time than expected and I had to abort it.

I read on HFSS document that whenever a project file is opened, two new files HFSS.auto and HFSS.lock is created automatically, so these are not due to wrong directory path or any other mistake. Its just they way, HFSS works as I could understand.