File Explorer

CloudMount for Windows uses the same technology as OneDrive: Windows’ Cloud Files API. Each drive you show in File Explorer becomes a sync root, a folder whose files are placeholders that download when you open them. CloudMount installs no kernel driver; Explorer, the file dialogs and every app see an ordinary folder, which can also have a drive letter.

Where your drives appear

• Each drive has its own folder at %USERPROFILE%\CloudMount\<drive name>, for example C:\Users\you\CloudMount\Google Drive. The location is fixed. CloudMount keeps it in your profile because Windows hides sync roots that live under AppData.
• Each drive also gets its own entry in Explorer’s navigation pane, named after the drive. Its icon shows the kind of drive: a cloud service, object storage (S3, B2, Azure, Google Cloud Storage, Swift), a server (SFTP, SMB, FTP, WebDAV, HTTP, HDFS), a local folder, an encrypted drive, or a vault.
• A new drive shows up in Explorer as soon as you add it. You can stop showing a drive at any time without deleting it (see Stop showing a drive).

On the free plan, one drive syncs in Explorer. Drives kept from Pro stay listed but can’t be opened until you go Pro or switch to them. See CloudMount Pro.

Drive letters

A drive can also have a drive letter, such as X:, chosen on its page in the app. X:\ then opens the drive’s folder, and shows up under This PC. Files open, change and sync through it as they do in the folder.

• Status icons, the Status column and the options to keep files on this PC or free up space show only in the drive’s folder, not under the letter.
• Apps run as administrator don’t see the letter.
• CloudMount never takes a letter that’s in use, such as a USB drive or a network drive. The app says so; free the letter and choose Try again.
• The letter goes when you stop showing the drive, and comes back each time you sign in.

Files on demand

Folders fill in when you open them, and files take no space on your PC until you open them.

• Listing a folder or reading a file’s properties downloads nothing, apart from thumbnails.
• Opening a file downloads it, progressively in 1 MiB steps, with a progress bar in Explorer. The downloaded data stays on your PC until you or Windows free up the space.
• Right-click → Always keep on this device downloads a file or folder and keeps it, also when its contents change on the drive. This needs Pro; on the free plan CloudMount undoes the setting and tells you so. The drive’s page in CloudMount lists everything you keep this way.
• Right-click → Free up space makes downloaded files online-only again. Files with changes that haven’t uploaded yet stay until they’re synced.

Microsoft Defender and large files

With Defender’s real-time protection on, Windows scans a cloud file completely before the app that opened it gets any data. Opening a large video therefore downloads the whole file first: in testing, a 1 GiB file took about a minute before it started playing. Streaming a file while it downloads isn’t possible through Explorer.

Status icons

Explorer’s Status column and the icons on each item show where a file is:

Icon	Meaning
Blue cloud	Online-only. It downloads when you open it.
Green tick in a white circle	Downloaded. You or Windows can free up its space.
White tick in a green circle	Always kept on this device.
Blue arrows	Syncing, or changes waiting to upload.
Couldn’t sync	CloudMount tried five times and failed. It keeps trying; the Activity page says why.
Conflict: both versions kept	The file changed both here and on the drive. Both versions were kept.

The last two are CloudMount’s own and appear only in the Microsoft Store version. They cover the first 1,000 waiting changes per drive, and are shown on the items themselves: a folder doesn’t show a problem inside it.

The CloudMount menu

Right-click a file or folder in a drive and open CloudMount for:

• Open in CloudMount: the drive’s page in the app.
• View sync status: opens the Activity page.
• Search in CloudMount, on a folder: searches that folder and everything in it, in the app. See Search.
• Copy public link: a link anyone can open without signing in, for backends that support public links (see the backend pages). CloudMount asks before creating one. Links on S3 and compatible storage expire after seven days.
• Version history…, on one file of an S3 or B2 drive: the file’s old versions, in the app, to restore one or save it as a copy beside the file. See Version history.
• Copy to… and Move to…: copy or move the selected files and folders to another drive, or elsewhere in the same one, without downloading them to your PC. See Copying and moving between drives.

Dragging files from one drive’s folder to another’s works too, but Windows then downloads every file to your PC and uploads it again, and the downloaded copies stay until you free up the space. For large folders, use Copy to… or Move to… instead.

Status flyout

On Windows 11 22H2 and later, the cloud button in Explorer’s address bar shows the drive’s state, how much of its quota is used (checked at most every ten minutes), and buttons to open CloudMount, pause or resume syncing, and see Activity.

Thumbnails

Online-only images and videos get thumbnails without being downloaded: CloudMount reads images of up to 32 MB, and decodes one frame from a tenth of the way into a video, two files at a time. Each drive’s page has a Thumbnails setting: Not on metered connections (the default), Always or Off. Downloaded files always get Windows’ own thumbnails.

There are no thumbnails yet for PDF and Office documents, comic archives or SVG files while they’re online-only.

Names Windows can’t use

Some names are valid on a cloud service but not on Windows:

• Characters Windows doesn’t allow in names, such as ?, : and *, and names that end with a dot or a space, appear with look-alike Unicode characters (for example ？ for ?). They keep their real names on the drive. This is rclone’s name encoding.
• Reserved device names such as CON, NUL or COM1 aren’t shown.
• When two names on the drive differ only in case, such as Notes.txt and notes.txt, only one is shown.

Hidden items are never deleted from the drive.

Search

Windows Search finds files in folders you’ve opened. Folders you’ve never opened haven’t been listed yet, so neither Explorer’s search box nor the Start menu can find what’s in them. To search whole drives, use Search in the app, or right-click a folder and choose CloudMount → Search in CloudMount to search that folder and everything in it.

When CloudMount isn’t running

Closing CloudMount’s window doesn’t stop syncing: the sync engine keeps running in the background. Quit CloudMount in the tray menu stops it. While it’s stopped, downloaded files still open, but online-only files can’t, and changes wait until CloudMount starts again. Opening a CloudMount folder in Explorer starts it again.