You purchase a 2 TB Google One cloud storage subscription with the goal of backing up your massive video projects, Raw camera footage, or 3D renders. You launch the official Google Drive for Desktop client, drag a 120 GB folder into your mounted Google Drive letter (G:\), and sit back. But minutes into the upload, Windows flashes an alarming red warning: "Low Disk Space: Drive C: is critically full." Your computer slows to a crawl, background applications crash, and the upload abruptly aborts.

This is one of the most widely reported headaches among digital creators: even though you are uploading files to the cloud, Google Drive for Desktop buffers a complete copy of every uploading file on your primary operating system drive (C:\) inside an internal cache folder. In this guide, we explain why Google Drive behaves this way and provide three concrete methods to upload massive files without filling up your primary SSD.

Why Google Drive for Desktop Fills Your C: Drive

Google Drive for Desktop operates primarily in one of two modes: Mirror files or Stream files. Most users select "Stream files" under the impression that files live purely in the cloud without consuming local disk space.

However, what the settings menu fails to explain clearly is the mechanics of the local staging cache:

  • When you drag files into the virtual Google Drive volume, the operating system treats it as a fast local filesystem write.
  • To prevent data corruption if your Wi-Fi fluctuates, Google Drive writes the entire file to a hidden cache directory on your system disk (usually %LOCALAPPDATA%\Google\DriveFS on Windows or ~/Library/Application Support/Google/DriveFS on macOS).
  • Only after the file is completely cached locally does the background sync service begin pushing chunks over the internet to Google's cloud servers.
  • If the size of your upload batch exceeds the available free space on your C:\ drive, the cache fills to 100%, causing Windows to freeze and Google Drive to halt with an I/O disk write error.

Method 1: Relocate the Local Content Cache Directory

If you have a secondary mechanical hard drive, larger gaming SSD, or external USB-C drive (e.g., Drive D:\ or E:\) with plenty of free storage, you can instruct Google Drive to store its cache on the secondary disk rather than your primary system drive.

Step-by-Step Instructions:

  1. Create a dedicated folder on your spacious secondary drive, for example: D:\GoogleDriveCache.
  2. Click the Google Drive icon in the Windows System Tray (near the clock) or macOS Menu Bar.
  3. Click the Settings gear icon in the top-right corner of the popup, and select Preferences.
  4. In the Preferences window, click the Settings gear in the upper right again to access advanced settings.
  5. Scroll down to the section titled Local cached files directory.
  6. Click Change and browse to your newly created folder (D:\GoogleDriveCache).
  7. Click Save and confirm the prompt to restart Google Drive.

Once restarted, Google Drive automatically moves its cache index. You can now upload files as large as the free space available on your secondary drive without ever threatening your primary Windows OS partition.

Method 2: Upload Directly via the Web Browser Interface

If your computer has only a single physical SSD and no secondary drive, the simplest way to avoid local caching is to bypass the Google Drive desktop client entirely.

When you upload files through the web interface at drive.google.com, Google Chrome and other modern browsers stream data directly from your source storage location through memory buffers to Google's servers using chunked HTTP POST requests. No permanent cache file is written to your C:\ drive.

  • Limitation: Web browser uploads can fail if your browser crashes, your laptop goes to sleep, or the upload exceeds 2,000 individual files. For massive multi-gigabyte files, keep your laptop plugged in and adjust power settings to prevent sleep mode.

Method 3: Cloud-to-Cloud Uploading with SaveInDrive

If your files originate from an external link, a remote server, another cloud provider (like Dropbox, OneDrive, or MEGA), or a direct HTTP download source, you should never download them to your local computer just to re-upload them to Google Drive.

Using SaveInDrive completely eliminates local disk consumption:

  1. Navigate to SaveInDrive.com.
  2. Paste the source URL or direct download link into the transfer console.
  3. Connect your Google Drive account and pick your target destination folder.
  4. Click Transfer to Google Drive. SaveInDrive streams the data directly from the host server into your Google Drive via high-speed cloud infrastructure. Your C:\ drive free space remains 100% untouched.

Method 4: Clean Out Orphaned Google Drive Cache Files

Even after uploads finish, Google Drive often fails to purge its local cache immediately, hoarding tens of gigabytes of disk space for weeks. If your C:\ drive is already full from past uploads, manually clear the cache:

On Windows:

  1. Exit Google Drive completely (Right-click system tray icon > Settings > Quit).
  2. Press Win + R, type the following path, and hit Enter: 
    %LOCALAPPDATA%\Google\DriveFS
  3. Inside this folder, you will see a subfolder named with a long string of numbers (your account ID). Enter it, locate the folder named content_cache, and delete its contents.
  4. Empty the Windows Recycle Bin, then relaunch Google Drive. You will immediately reclaim tens of gigabytes of SSD capacity.

On macOS:

# Quit Google Drive, then execute in Terminal:
rm -rf ~/Library/Application\ Support/Google/DriveFS/*/content_cache/*

Advanced Method: Relocating Cache via NTFS Junctions (Symlinks)

If your organization manages your computer and locks down the Google Drive Preferences interface, you can force cache redirection at the operating system level using an NTFS directory junction:

  1. Exit Google Drive completely from the system tray.
  2. Move the existing cache folder to your secondary hard drive: 
    move "%LOCALAPPDATA%\Google\DriveFS" "D:\DriveFSCache"
  3. Create an NTFS directory junction pointing from the default system location to the secondary drive: 
    mklink /J "%LOCALAPPDATA%\Google\DriveFS" "D:\DriveFSCache"
  4. Relaunch Google Drive. Windows will seamlessly redirect all low-level write operations to drive D:\, ensuring your primary SSD partition never runs out of space during heavy uploads.

Does Clearing the Local Cache Delete Files in the Cloud?

No. Deleting files inside the local content_cache folder does not affect files that have already successfully synced to Google Drive's cloud servers. The cache serves merely as a temporary local staging buffer. Once an upload status confirms "Sync complete", Google Drive retains the master copy securely in the cloud.

Summary

Google Drive's local caching behavior is intended to safeguard data against network dropouts, but it poses a major obstacle when uploading large files on space-constrained SSDs. By relocating your cache directory to a secondary drive, uploading directly through the browser, or leveraging cloud-native transfer tools like SaveInDrive, you can transfer massive files smoothly without ever crashing your primary operating system drive.