1. less than 30MB 2. I don't open file directly. I have imported the files in QM as symbols. All data is small that I can open them in 5 sec in normal situation. 3. Yes, it does happened after I change symbol settings. Such as change time frame or session setting. 4. I have tried waiting for 3 hrs. ...

I have exact the same problem, too. The situation is as follow : I have 2 workspace, workspace_B is duplicated from workspace_A, which only have 2 ascii instruments in it. I take workspace_A as a backup. And I play things in workspace_B, such as test some study/indicator, change instruments. Suddenl...

I like this idea.
Is that only MC.NET can do this?
Can MC do this too?