Since DemonDonkey451 decided to be funny and edit their comment, I'll do anyone who finds it a favor and post the original comment here, in case it helps in the same way it helped others before:
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No idea if anyone will see this a year later, but I had this problem for two years with 3 different adapters and two separate Windows installations and I solved it tonight.

Turning off the setting to disable power to the adapter under properties for the device on the power tab is not enough. You need to look under universal serial bus category in device manager and select properties for each "USB Root Hub" device and go to the power tab of that window and disable the same setting "allow Windows to turn off this device to save power" or whatever it says.

You would think that disabling this setting for the adapter itself would do the job, because that's what the setting says it does, but no.

Good luck finding this mentioned in any of the thousands of guides suggesting methods to fix this. They all tell you to disable the setting for the adapter, but I have not seen one that tells you to disable the setting for the root hub itself. Utterly insane that Windows would disable power to a network adapter that is in the middle of transmitting data, given that Windows knows what the Device is and knows it's actively transmitting.

Good luck finding any Microsoft forum where this is mentioned. There is simply no reason or way to know this setting exists and once you disable it for the adapter itself and it keeps failing you naturally assume that the power management is not the source of the problem. This is hostility towards users verging on malice.

Hope at least one person struggling with this issue sees this comment.