iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
My C: drive kept running out of space, but the useful answer wasn’t a guess about one mysterious Windows folder: it was to check which storage category was growing, then deal with that category. Windows’ storage tools can point you toward apps, temporary files, system files, or personal files; they do not identify the cause on their own.
Find what is using space on C:
-
Open File Explorer > This PC and check the available space on the Windows drive. It is usually C:.
-
Open Settings > System > Storage. Windows groups usage into categories such as Installed apps, Temporary files, and System & reserved. Start with the largest category, but treat it as a lead for investigation rather than proof of a specific cause. Labels and available controls can differ between Windows 10 and Windows 11. See Microsoft’s Storage settings in Windows guidance.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
Special offer. See more information about Outbyte and uninstall instructions. Please review EULA and Privacy policy. -
Open the relevant category or Cleanup recommendations, where available, and review the items before removing anything. Microsoft says Cleanup recommendations can surface temporary files, large or unused files, cloud-synced files, and unused apps. Details are in Free up drive space in Windows.
#1 Best Overall
Sandisk 2TB Extreme Portable SSD, Up to 1050MB/s, USB-C, USB 3.2 Gen 2, IP65 Water and Dust Resistance, Updated Firmware, External Solid State Drive, SDSSDE61-2T00-G25- Get NVMe solid state performance with up to 1050MB/s read and 1000MB/s write speeds in a portable, high-capacity drive(1) (Based on internal testing; performance may be lower depending on host device & other factors. 1MB=1,000,000 bytes.)
- Up to 3-meter drop protection and IP65 water and dust resistance mean this tough drive can take a beating(3) (Previously rated for 2-meter drop protection and IP55 rating. Now qualified for the higher, stated specs.)
- Use the handy carabiner loop to secure it to your belt loop or backpack for extra peace of mind.
- Help keep private content private with the included password protection featuring 256‐bit AES hardware encryption.(3)
- Easily manage files and automatically free up space with the SanDisk Memory Zone app.(5). Non-Operating Temperature -20°C to 85°C
If personal files are taking up the space
Check Downloads, Videos, Music, and Pictures for large files. In File Explorer, open a folder and sort its contents by size to find the biggest space users first. Delete items you no longer need, or move files you want to keep to connected external storage. Files sent to the Recycle Bin still occupy disk space until you empty it.
If new downloads or other content keep accumulating, Windows lets you change where new content is saved. External storage is most useful when personal files are the main space consumer and you want to retain them; it is not a substitute for checking what is actually filling the drive. Microsoft covers moving personal files and save locations in its drive-space guidance.
Rank #2
- Solid state performance with up to 800MB/s read speeds in a portable drive. (Based on internal testing; performance may be lower depending on host device, interface, usage conditions and other factors. 1MB=1,000,000 bytes.)
- Back up your content and memories on a storage solution that fits seamlessly into your mobile lifestyle.
- Take it with you on your adventures—up to two-meter drop protection means this durable drive can take a beating. (Based on internal testing.)
- Secure it to your belt loop or backpack for extra peace of mind thanks to the tough rubber hook.
- From Sandisk, a brand professional photographers trust to take on assignments.
If temporary files or an old Windows installation are taking up space
Review Settings > System > Storage > Temporary files or Cleanup recommendations, depending on your Windows version. Read each item’s description and select only what you intend to remove. Disk Cleanup is also included in Microsoft’s Windows 10 guidance; its Clean up system files option can reveal additional cleanup choices.
PC Slower Than It Used to Be?
A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11Crashes, No Sound, or Screen Glitches?
Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minutePay particular attention to Previous Windows installation(s), often associated with the Windows.old folder. Removing it can take away the option to return to the previous Windows version. Treat that as a rollback decision, not routine cleanup; Microsoft explains the consequence in its cleanup instructions.
Rank #3
- Capacity Display Variance: 500GB external ssd often appears as around 465GB on Windows. MacOS can show full 500 GB capacity. This is binary calculation difference and doesn’t affect SSD hard drive actual physical storage
- 1050 MB/s Speed: Instantly access to your files with blazing-fast 10Gbps external SSD read up to 1050MB/s and write up to 1000MB/s. LED Light indicates USB SSD instant activity
- Data Security: Solid state drives S.M.A.R.T. health diagnostics and adaptive TRIM optimizing data block management ensures consistent write speeds and extends the longevity of the portable SSD
- USB-C & USB-A Cable: Both cables featuring rapid USB 3.2 Gen2, this USB SSD effortlessly bridges devices, enabling seamless cross-platform file transfers and backup between computers, smartphones, tablets and iPhone
- Always Fast: No slowdowns for large file transfers. With SLC caching (25% of current available capacity allocated as high-speed cache), this external SSD delivers steady 10Gbps for transfers within the cache capacity
If apps are taking up the space
Use the Installed apps category or Cleanup recommendations to identify apps you do not use. Uninstall only apps you recognize and no longer need. The category helps show that apps are a significant part of usage, but it does not tell you which app is safe for you to remove.
Configure Storage Sense instead of assuming it cleans everything
Storage Sense can automate selected cleanup on the system drive, usually C:, but what it removes depends on its settings. Microsoft describes its scope this way: “Storage Sense works on your system drive only, which contains the Windows operating system and is usually referred to as C:.” Review its configuration under Settings > System > Storage > Storage Sense; exact labels may vary by Windows version.
Rank #4
- Easily store and access 2TB to content on the go with the Seagate Portable Drive, a USB external hard drive
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
Check the configured run frequency and the options for Recycle Bin, Downloads, and cloud content. By default, Downloads and cloud content are not managed unless you set those options. In Windows 11 version 22H2, Microsoft says eligible OneDrive files can become online-only after 30 days by default; user settings and Always keep on this device affect that behavior. Online-only files remain in OneDrive but need an internet connection to download when opened. See Microsoft’s Manage drive space with Storage Sense documentation.
If space disappears again after cleanup
First check Storage again and see which category has grown. If the Temp folder is repeatedly filling with Microsoft Store .appx files, Microsoft documents a specific troubleshooting path: reset the Store, clear its cache with wsreset.exe, run the Windows Store Apps and Windows Update troubleshooters, and restart the PC. This branch applies to that reported Temp-folder pattern; it is not a general explanation for every recurring low-space warning. Follow the steps in Microsoft’s drive-space troubleshooting guidance.
Best Value
- MADE FOR THE MAKERS: Create; Explore; Store; The T7 Portable SSD delivers fast speeds and durable features to back up any endeavor; Build your video editing empire, file your photographs or back up your blogs all in an instant
- SHARE IDEAS IN A FLASH: Don’t waste a second waiting and spend more time doing; The T7 is embedded with PCIe NVMe technology that brings fast read and write speeds up to 1,050/1,000 MB/s¹, making it almost twice as fast as the T5
- ALWAYS MAKE THE SAVE: Compact design with massive capacity; With capacities up to 4TB, save exactly what you need to your drive – from large working files to game data and everything in between
- ADAPTS TO EVERY NEED: Whether using a PC or mobile phone, count on the T7 for extensive compatibility²; It’s a true team player when it comes to heavy-duty application usage or file-saving
- HI RESOLUTION VIDEO RECORDING: Record Ultra High Resolution (4K 60fs) videos directly onto the T7 Portable SSD with your favorite camera or mobile devices; Supports iPhone 15 Pro Res 4K at 60fps video and more³
If Windows needs space for an update
Update storage needs vary by device, installed content, and the update. Microsoft does not give one universal free-space minimum. If Windows asks for temporary storage during an update, an external storage device may reduce how much free space is needed on the system drive. See Free up space for Windows updates for the update-specific process.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
