This has happened too many times. I am editing songs after recording from a cassette tape. I go away for awhile. When I come back to resume editing, as soon as I click in the window, I get the “not responding” message. I have to shut down the program. When I re-open the program, It offers to restore the file I was working on. But when I say yes, it brings up a straight, horizontal line with nothing in it. I am using 2.1.0 with Win 10 and 16GB RAM. What is going on and how can I eliminate this problem?
Just to cover it:
The machine did not go to Sleep or Suspend, right?
Are you connected to wall power or batteries?
How did you transfer your cassette? In detail. Part numbers.
What’s the goal? “I want to burn an Audio CD.”
Koz
I recommend you use Audacity 2.1.2 from http://www.audacityteam.org/download/windows. With that version, the temporary files when you have not yet saved a project will not be liable to deletion by cleanup tools, which would be one explanation for the flat line.
The safest thing to do would be to File > Close the project (say Yes to saving changes) when you leave and reopen the project from File > Recent Files when you return.
Gale
When you see the “not responding” message don’t immediately assume that the application is dead. Windows (starting with 7, I think) automatically puts inactive applications “to sleep” to conserve operating system resources. Windows determines “inactivity” based on user input primarily but passing function off to an external library/application might also look like inactivity. After Windows puts an application to sleep then notices user input for the application it tries to wake up the application by sending it a message; sometimes it takes quite a while for the application to wake up and reply to Windows that it is awake; during this time you will see the “not responding” message. I would suggest that when you see this “not responding” message you wait as much as two minutes to see if the application starts responding again. One good indication that the application is not really “frozen” is to click on the minimize button; if the application minimizes it may well come back from “not responding”. Go check your email then restore the application backup to see if it is now functioning.
Is any per-application throttling-when-idle that Windows does documented anywhere, Ed? I’d be surprised if it didn’t do something along those lines, but I don’t recall ever reading anything about it.
Of course if the machine is waking after hibernation, this does take time because the system state has to be read back in from the hibernation file on the drive.
Gale
Is any per-application throttling-when-idle that Windows does documented anywhere, Ed?
I don’t know of any specific documentation.
from the hibernation file on the drive.
And that’s the exact place it’s good to know if the drive is spinning metal or SSD. I would expect an SSD to wake back up again in the one or two second region.
Koz

from the hibernation file on the drive.
And that’s the exact place it’s good to know if the drive is spinning metal or SSD. I would expect an SSD to wake back up again in the one or two second region.
Koz
My high-end SSD drive DOES NOT wake up quickly; with the exception of the external USB four terabyte drives it’s by far the slowest; my internal hard drives vary in size and age but all respond fairly quickly (10 seconds or so) the SSD is closer to 30 seconds and the external drives more like 45 seconds.
my internal hard drives vary in size and age but all respond fairly quickly (10 seconds or so) the SSD is closer to 30 seconds
I’d call that broken. To read that back to you, ‘my mechanical drives which are horsing several heavy, mechanical heads and arm assemblies over a platter assembly which takes several seconds to spin up from a dead stop, is faster than accessing a memory chip.’
I accidentally got to experience an A/B test once. One of the guys in IT had almost an identical laptop to mine except he had spinning metal and I had an SSD. I had occasion to use his and I thought it failed. It was like wading into cold treacle/molasses. “No,” he said, “That’s normal.”
Correct me, but Audacity is a single-processor, 32-bit application? So at best it’s going to lag behind other applications and processes. But that doesn’t account for getting rapidly into and out of standby, sleep, suspend, etc. That should be a system function.
Koz
Thanks for all of your comments. My desktop didn’t go to sleep, hibernate, or suspend. It is plugged into the wall. The last time this incident occurred I went away for 10 minutes. When I returned, the little blue circle was still spinning and the ‘not responding’ message was still there. Clicking the X button didn’t even work. I have a Pioneer cassette deck plugged into an Onkyo receiver that is then plugged into my computer. I have used this setup for a long time with good results.
As for Audacity, I have never been able to recover a file once it hangs up. I will try version 2.1.2 and see if it does any better. My last attempt at copying a cassette into Audacity ended with the first side being flatlined and the second side remaining. My cassette player has an auto-play for both sides so I don’t have to manually turn it around.

The last time this incident occurred I went away for 10 minutes. When I returned, the little blue circle was still spinning and the ‘not responding’ message was still there.
That sounds like you were running an effect or doing something when you left that was still completing when you came back.
When you install 2.1.2, half way through installation, you will see a checkbox “Reset Preferences”. Check (tick) that box. When you launch Audacity, say yes to resetting preferences. That might help.
Gale