HowTo: Free up some disk space by disabling hibernation on Windows 10

I have a small older Tablet PC (Lenovo S10-3t) that I’m running Windows 10 on, having replaced its internal classic SATA hard disk with an SSD one, and since SSD space is scarce (being more expensive I got a smaller in size disk than the original one), I needed to make free space.

Since that machine is always connected to power, connected to a monitor mounted on the wall (and turned into tent mode in front and under the main monitor, to use it as a second touch-enabled screen for app testing), I don’t really need to use hibernation (after all its battery has gone dead, so hibernation won’t get a chance to occur in the case of an electrical network power down anyway).

That could save some extra disk space, since when hibernation is enabled, you end up with a hiberfil.sys file in the root folder of the boot disk that has around the size of the memory on your computer (or at least that was the case before Windows 10, since I was seeing an 850MB file although the computer has 2GB memory).

To cut it short, I looked it up and found this relevant Microsoft article:
https://support.microsoft.com/en-us/kb/920730

However, the automated way it suggests (the FixIt app) doesn’t seem to work on Windows 10 (probably neither on Windows 8, it doesn’t list it at the bottom of the page anyway) and one has to use the manual way. On Windows 10 the quickest way (based a bit on the suggestions in that article), is to right click the start menu button at the bottom-left of your screen and select “Command Prompt (Admin)” at the popup menu. Then reply affirmatively at the User Access Control (UAC) prompt shown and at the command prompt (a dark console window) that appears, type powercfg.exe /hibernate off and press the ENTER key. Then just close the console window and check the “This PC” node at the File Explorer to confirm that you saved some extra hard disk space.

Fix: Cleanup after upgrading from Windows 10 technical preview

I recently replaced the internal hard disk of my old Lenovo S10-3t Tablet PC with an SSD and installed Windows 10 technical preview, but recently realized the hard disk had almost run out of space.

Trying to figure out why, I realized that upgrading from the Windows 10 technical preview version to the final Windows 10 version (this happened automatically via Windows Update), left back a “Windows.old” folder at the hard disk root taking up 3.14GB, as if I had upgraded from Windows 7 or Windows 8 via Microsoft’s free OS upgrade offer (that offer is valid for a year btw, so make sure you don’t miss it).

You’ll notice the Disk Cleanup tool (you can find it by pressing the search icon (magnifying glass) at the Windows taskbar and writing “cleanup”, temporary Windows installation files are also mentioned as taking up an extra 3.22 GB, but there is some double counting there, since I ended up with 5.30GB free after cleanup, from around 200MB I had left on the hard disk before I run Disk Cleanup (note that I already had run CCleaner, but I hadn’t selected the option there to cleanup files from previous Windows installation, since I didn’t expect to have any such).

Note, that Disk Cleanup will even warn you that you won’t be able to restore the machine back to the previous Windows version (aka the technical preview), but why should you care to do so anyway?

Update:

To make some extra disk space and since I use a fast SSD, I had set Windows to compress the hard disk contents (one can set this option by right clicking the disk and selecting Properties), so probably there is no double-counting by Disk Cleanup dialog, it just must be showing the uncompressed space those things it cleans take up. So it could indeed be 3.14GB + 3.22GB of useless space taken up by updating Windows technical preview to the official Windows 10 release via the normal automatic Windows Update process, which is quite a lot.

Microsoft should show some warning to the user about all this extra space taken up (right away after updating and offer to remind them in the future again if they opt to keep the files till they’re confident the latest version works OK) and offer them the choice of cleaning this up

Another interesting thing I notice is that although I had selected the option to compress the drive and it had applied respective attribute to all files (showing a progress dialog), it didn’t remember that setting (not sure if I had set it before the upgrade), so probably it wasn’t compressing newer files.