I have added this issue to the tracker:
Bug 2083 – Workaround for an apparent bug in Windows 11 that prevents WinSCP from stopping Windows going to the sleep mode during transfers

Completed and I've sent you a reply mate.

@Bazza: I have sent you an email with some test applications.

@martin: Cheers. I'm sure you'll get to the bottom of it.

@Bazza: I can indeed reproduce the problem on Windows 11.
But I do not know why it's not working.
I've asked a question on Stack Overflow:
SetThreadExecutionState(ES_SYSTEM_REQUIRED) does not prevent system sleep on Windows 11

I'm running Windows 11 Pro and you're running Windows 10? Not sure what else could be different.

I cannot reproduce it.

WinSCP 5.19.6 (latest stable)
Windows 10 (Pro) 21H2/19044 (latest stable)

In Windows 10 Settings app I set the PC to go to sleep after 1 minute.

I run WinSCP. When I keep it idle, the PC goes to sleep after 1 minute+.

I start an upload of set of files, that take about 2-3 minutes. As long as the files are transferring the PC does not go to sleep. It does only about 30-40 seconds after the upload finishes. No difference between foreground and background uploads. Tested several times with the same results. SFTP session.

No difference between a regular installation and Windows Store installation.

Where do we differ?

martin wrote:

@Bazza: Are you also using the Store installation?

No I downloaded from here.

@Bazza: Are you also using the Store installation? + Your transfer was put to the background queue, is that correct?

I've just experienced the same issue. I had a 5 hour queue so left it transferring overnight. Woke up this morning and Windows 11 had gone to sleep before the first file had completed downloading. I've had to turn sleep off in Windows to prevent it happening until a fix is found.

@just-a-user: I'll look into it.

Yes, that is correct.

@just-a-user: Do you mean that Windows automatically goes to sleep mode despite an ongoing transfer?

I have the same problem. Background transfer, Windows 11 with the app from the Microsoft store. Is there a setting to prevent this? I couldn't find one.

I know that you are using "background" transfer. You have mentioned that in your first post already.
And I wrote that "A transfer prevents the sleep. Both foreground and background."
I cannot reproduce your problem unfortunately.

As I started on my dad's computer, I realized what may be an important detail. I am using the WinSCP background queue for transfer. If transfers are happening in the queue (instead of the foreground), do the no-sleep features take effect?

I do not think I have any unusual settings configured.
Windows 10 sleep settings are pretty simple.

I don't have ready access to the computer with the issue (it is my mother's, and it's about 1000 miles away). But, it was happening in just a few minutes (about 10 minutes, I think), and it corresponded with screen blanking and apparent sleep mode from what I could see.

I'm about to have another test of an almost identical system (my dad's computer broke, too, and we got him the same model laptop as my mom). I anticipate that it will go to sleep while we are transferring his many GB of pictures back to his new computer. Do you have specific recommendations of what I should do to test it more effectively? Are there any Windows settings that I should look for or report for those transfers?

For me it seems to work correctly.
A transfer prevents the sleep. Both foreground and background.
I didn't test it "overnight", just for few minutes. Windows goes to sleep only after the transfer completes and Sleep interval elapses after the transfer.
Are you able to reproduce the problem, when you set Windows Sleep interval to few minutes?

@martin: Thanks! In case it helps, the computer is a new Windows 10 laptop with all current updates applied.

WinSCP should prevent the sleep. I'll look into it.

Yes, based on what I saw in Sleep during transfers, I expected WinSCP to prevent the computer from going to sleep. As I'm thinking about it more, I think that it should only be an option for a transfer (and not a requirement), so perhaps a checkbox like "prevent computer from suspending or going to sleep during transfer" would help.

If that's not in scope for WinSCP, that's OK.

I'm not sure what is the question.
Did you expect WinSCP to prevent the computer from going to sleep?

Thank you for the great software!

I setup my mother's computer to download lots of kid pictures from me (about 30 GB in a single zip file). We set it up as a background transfer, and left it to go overnight. Her computer went to sleep, and the transfer paused. When she started using the computer again, the transfer restarted.

I think that this is similar to https://winscp.net/forum/viewtopic.php?t=5867, but I'm not sure if it's something different with Windows 10, background transfers, or something else. Is a pause during a background transfer expected?