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Problem 1: Lack of free space.

Press Windows key + R
Type: C:WindowsLogsCBS
Hit Enter

Delete any log files found in that folder.

Click Start > Settings > System > Storage
Under Storage sense, click Free up space now

Wait while it scans for temporary files.

Check any location with large amounts of space.

Click Remove files.

Also see how you can use TreeSize to find and free up space:
https://www.groovypost.com/howto/map-hardrive-usage-find-hidden-files-Windows-10-treesize-freeware/

Search through any folders that might be on your desktop that might be taking up space. 

Options for freeing up space:

Windows over time will accumulate data outside of the normal types of data we store. This can include things like copies of Windows Updates, memory dump files used to diagnose and troubleshoot error messages, temporary internet files for web pages we often visit and Windows Upgrade files, commonly used to assist with installing updates for Windows. Sometimes we don't need this type of information and removing it can free up precious disk space inaddition to improving overall system performace.


Having enough disk space is especially important if you are performing task such as upgrading to the new Windows 10. It is one of the the first things Windows setup checks before it starts copying files. Large programs too will often require that you have enough disk space available.

Lets start.

Launch Disk Cleanup, the quickest way is this:

Press Windows key + R then type: cleanmgr.exe

Then hit Enter


Windows 10 > Start > All Apps > Windows Accessories > System Tools > Disk Cleanup

Once Disk cleanup opens, select the drive where Windows is installed if its not already.

Windows will scan your hard disk for files it can clean up.

Note some of these files too can include older installations of Windows. For example, if you upgraded from a previous version of Windows 10, a copy will be kept at the root of the hard disk in a folder called Windows.old. Please becareful though, this folder can actually be useful if you need to go back to your previous version of Windows for whatever reason. So be mindful before deleting it. Removing it though can significantly free up disk space.


After Disk Cleanup is finished scanning, you will see the Disk Cleanup window. This window provides a list of areas of the system you can clean up safely. Before we start cleaning up the system, you will notice appears on the window called Clean up system files. Clean it and the Disk Cleanup will run a thorough check of the system again to include every file that can be removed.

Location/Type 	Description 	Safe to Delete

Downloaded Program Files 	Downloaded Program Files are ActiveX controls and Java applets downloaded automatically from the Internet when you view certain pages. They are temporarily stored in the Downloaded Program Files folder on your hard disk. 	YES

Temporary Internet Files 	The Temporary Internet Files folder contains webpages stored on your hard disk for quick viewing. Your personalized settings for webpages will be left intact. Personally, I suggest you keep this if you are on a slow connection and need the basic elements of web pages you often visit to load faster. 	Keep It

Offline Webpages 	Offline pages are webpages that are stored on your computer so you can view them without being connected to the Internet. If you delete these pages now, you can still view your favorites offline later by synchronizing them. Your personalized settings for webpages will be left intact. I also recommend you leave this alone since you might be on a slow connection and need quick access to a webpage with some specific content. 	Keep It

Recycle Bin 	The Recycle Bin contains files you have deleted from your computer. These files are not permanently removed until you empty the Recycle Bin. Sometimes you might inadvertently delete a file that you didn’t intend to delete permanently, so before you empty the contents of the Recycle Bin, do a thorough check before. 	YES

Temporary files 	Programs sometimes store temporary information in the TEMP folder. Before a program closes., it usually deletes this information. You can safely delete files that have not been modified in over a week. You can view the contents of the temp directory and see if there is anything in there you might need. Open the Run Command (Windows key + R), type in %temp% > hit OK. Sometimes program installers for common applets are stored there that you can use to reinstall such as Adobe Flash for instance if you don’t want to redownload it every time. 	YES

Thumbnails 	Windows keeps a copy of all your picture, video, and document thumbnails so they can be displayed quickly when you open a folder. If you delete these thumbnails, they will be automatically recreated as needed. I don’t see any problems deleting it if its gonna be recreated, but deleting it sometimes can correct problems with previews of photos and videos. 	YES

Debug Dump Files 	When your computer experiences a system hang because of a poorly written application or device driver, Windows intelligently creates a log of what happened. This log can be used along with other logs such as System error memory dump files to help diagnose the problem when sent to Microsoft or the developer for review. 	Keep It

System error memory dump files 	Similar to the Debug Dump files, memory error dumps happen when poorly written drivers or applications crash. It is very handy for utilities built into Windows such as Troubleshooters which help in diagnosing problems that occur in Windows. 	Keep It

 The most common locations are Temporary files, Temporary Internet Files, Recycle Bin to name a few. Other not so common locations include the Thumbnail Cache which stores previews of your images allowing you load them faster when you open the Pictures Library or Windows Live Photo Gallery. This I do not recommend you delete for obvious purposes. Lets dig a little deeper. Disk Cleanup provides a list of areas where you can free up disk space and gain additional speed in some cases.

In addition to these common locations, Windows will also store information related to Error reporting and solution checking, leave these for diagnosis that can help resolve issues with applications or devices. Also, if you do an upgrade from previous version of Windows 10 or clean install, Windows 10 might store information related to servicing which are logs used to assist the installation of the operating system. Once you have checked these locations for clean up, click the OK button and these locations will be cleaned out.

As I noted earlier, the Windows.old folder is basically a backup of your old installation of Windows, which you can use to reinstall Windows if you decide to return to your previous installation. Also, its used as a last resort in case you didn’t backup your files and need to recover personal files and settings. The Windows.old folder can use up a considerable amount of your hard disk space. Its normally stored at the root of your hard disk where Windows 10 is installed. Before you delete it, make sure you check through the directories and ensure that everything migrated successfully to your current version of Windows.

How to Recover Documents, Music and Email After Upgrading with the Windows.old folder



Once you have determined what to remove, click OK then click the Delete Files button to begin.

Click Yes if you are ok with the action that will be taken.

System Restore – System Restore keeps a large collection of System Restore Points in addition to storing them in your System Images of Windows 10. A friend had recently upgraded to Windows 10 and he asked me why he was low on hard disk space. He had a 320 GB drive and only had about 70 GBs of free disk space left after doing a disk cleanup. It was then I discovered that System Protection had been configured to use about 200 GBs of  disk space to keep System Restore Points.

Configuring System Protection settings

To configure System Protection, click Start, type: System Protection, hit Enter. Under Protection Settings, click the Configure button. A dialog will appear with various settings for configuring Restoration and Disk space usage. Under the Disk space usage tab, you will see the current amount of space in use by System Restore while the Max usage displays the amount allocated. 

Use the Max usage knob to configure how much disk space you want to allocate to System Protection. In the above screenshot, you will see that I am using 21.05 GBs for Restore Points, while I have allocated 22.36 GBs of disk space for System Protection. You also have the option of deleting all Restore Points which stores System settings and previous versions of files. I suggest you leave this, since you will be able to individually restore changes to files you are working on. So for instance, if you edited an image and would like to restore it to a previous version or original version of the file. 

Archive Large Files to an External Hard Disk

Storing large files on your local drive that you are not using doesn’t really make much sense these days. Moving infrequently used multimedia, like photos and videos, to an external drive can free up significant amounts of disk space.  Because of my Internet limitations, I still need to keep my music locally, so that means my iTunes library probably consumes the most space on my Surface Pro.

Archiving files to an external drive is easy. Before you do that though, you need to invest in an external drive. It’s fairly easy to find one that is really cheap with lots of space.  Once you have one, I recommend you check out our guide on how to partition a hard drive for macOS Time Machine and Windows 10 Backups.

There are several backup methods you can use, but I always go with the manual method, which involves copying files from your personal folder to a backup folder on your external drive. Select the files or folders then performing a drag and drop action using the right mouse button to your external drive. When the context menu appears, click Move here.

source: https://www.groovypost.com/howto/maximize-storage-Space-low-capacity-Windows-10-devices/