Download and Installation

Downloads

OS	OS Requirement	Download Link
Windows	Windows 7 32/64-bit or above, Windows Server 2008 R2 64-bit or above	Windows
macOS	macOS 10.13 or above	macOS
Linux	Includes GUI and supports the AppImage format	Linux
Website version	Browsers such as Chrome, FireFox, Safari, and IE10+	Web

Installations

The COSBrowser installation package is an executable file. You can double-click the downloaded file and then install as prompted.

Note：

To launch the client running CentOS, you need to run ./cosbrowser.AppImage --no-sandbox in the terminal.

Login

You can log in to the COSBrowser desktop version using a permanent key, Tencent Cloud account, or a shared link. You can log in to an account on multiple devices at the same time.

Login with a permanent key

You can log in using your Tencent Cloud API key (SecretID and SecretKey), which can be created and obtained at Manage API Key in the CAM console. After you logged in successfully, the key will be saved to Historical Sessions. The login page and configuration items are as follows:

• Bucket/Access Path: If this field is specified, you can quickly navigate to the specified path. This field is required if the key only has permission to a certain bucket or a certain directory. The format is Bucket/Object-prefix (for example, examplebucket-1250000000 or examplebucket-1250000000/folderName).
• Description: description of the permanent key entered, such as the operator and the usage. The description can be used to distinguish different SecretID when you manage the historical sessions on the historical key page.
• Remember Session：
  • If this box is not checked, the Tencent Cloud API key entered will be cleared when you log out (if the key has been saved to the historical sessions, it will be removed).
  • If this box is checked, the Tencent Cloud API key entered will be remembered and can be managed in the historical sessions.

Note：

You can not log in to COSBrowser with a project key.

Login with a Tencent Cloud account

Click Tencent Cloud Account Login and log in to the COSBrowser desktop version in the pop-up window. This login method supports WeChat, email, QQ, WeChat Official Account, WeCom, and sub-account logins.

Login with a shared link

The Share Folder feature can generate a link and password, with which you can log in to the COSBrowser desktop version temporarily.

Basic Features

1. Creating/Deleting bucket

Feature	Description	Directions
Creating bucket	You can create a bucket directly via the client	1. In the bucket list, click Add Bucket in the upper-left corner 2. Enter the bucket name correctly, and select your region and access permissions 3. Click OK
Deleting bucket	Before you delete a bucket, ensure that all data in the bucket has been cleared	1. In the bucket list, click Delete on the right of the selected bucket 2. Click OK

2. Viewing bucket details

You can view bucket details by clicking Details on the right of the bucket list. Details include bucket name, region, access permissions, and versioning status.

3. Viewing statistics

You can click … > Statistics to view the bucket statistics, including the storage usage and the number of objects.

4. Managing permissions

You can use COSBrowser to manage permissions for buckets and objects.

• Bucket permissions: Click Permission Management on the right of the bucket list.
• Object permissions: Click Permission Management on the right of the object.

Note：

For more information about COS permissions, please see ACL Overview.

5. Setting versioning

You can use COSBrowser to enable/disable versioning for a bucket.

To configure versioning, click Versioning on the right of the bucket list.

Note：

For more information about versioning, please see Versioning Overview.

6. Adding an access path

If you log in with a sub-account that does not have permission to access the bucket list, you can initiate an access via Add Access Path in the following two ways:
(1) Add an access path directly on the login page and select the corresponding bucket region. Once you log in, you can manage your resources.

(2) Log in with your sub-account, click Add Path in the upper-left corner of the bucket list page, and enter a specified path to enter the bucket and manage its resources.

7. Uploading file/folder

Upload Feature	Description	Directions
Uploading files	COSBrowser allows you to upload a single file or multiple files in batches in different ways.	You can upload files in the following ways. In the specified bucket or path: 1. Click Upload Files to upload files directly. 2. Right-click in the blank space of the file list and select Upload Files to upload files. 3. Drag a file to the file list pane.
Uploading a folder and the files contained	If the name of the file/folder to upload already exists in the bucket or path, the old file/folder will be overwritten by default.	You can upload a folder in the following ways. In the specified bucket or path: 1. Click Upload Folder to upload a folder directly. 2. Right-click in the blank space of the file list and select Upload Folder to upload a folder. 3. Drag a folder to the file list pane.
Incremental upload	Incremental upload compares the files to upload with existing files in the bucket before the upload. An existing file with the same name in the bucket will be skipped.	You can perform the following 2 steps to use incremental upload. In the specified bucket or path: 1. Upload as you do with a folder and click Next. 2. In Storage method, select Skip. Then, click Upload to begin the incremental upload.

Note：

If you need to upload files in batches, you are advised to use a computer with a 4-core CPU and 16 GB RAM, which allows you to upload up to 300 thousand files at a time.

8. Downloading file/folder

Download Feature	Description	Directions
Downloading files	COSBrowser allows you to download a single file or multiple files in batches in different ways.	You can download a file in the following ways: 1. Select the desired file and click Downloadin the UI. 2. Right-click the file and select Download. 3. Drag the file to the local file system.
Downloading a folder and files contained	If the name of the file/folder to download already exists in the local file system, it will be renamed by default.	You can download a folder and the files contained in the following ways: 1. Select the desired folder and click Download** in the UI. 2. Right-click the folder and select Download. 3. Drag a folder to the local file system.
Incremental download	Incremental download compares the files to download with local files before the download. An existing file with the same name will be skipped.	You can perform the following 3 steps to use incremental download: 1. Select the desired file/folder, move the mouse to More, and a drop-down list will appear. 2. Click Advanced Download in the drop-down list and select Skip in the dialog box. 3. Click Download Now to incrementally download new files/folders.

Note：

If you need to download files in batches, you are advised to use a computer with a 4-core CPU and 16 GB RAM, which allows you to download up to 300 thousand files at a time.

9. Deleting file/folder

To delete a file/folder, select the file/folder to delete and click Delete in More at the top of the UI, or right-click it and select Delete. You can delete multiple files/folders in batches.

10. Synchronizing file

The file synchronization feature allows you to upload specified files in your local folders to a bucket in real time. Detailed directions are as follows:

(1) Click Sync in the upper right of the UI.
(2) Specify a local folder and bucket directory in the dialog box.
(3) Click Start Sync to enable file synchronization.
(4) View synchronization history logs in the Sync Logs tab.

Note：

• Synchronization means that when the file is uploaded, the system automatically identifies whether the same file exists in the bucket. Only files that do not exist in the bucket are synchronously uploaded.
• Currently, only synchronizing local files to the bucket is supported. Reverse operation is not supported.
• Both manual and automatic synchronization are supported.

11. Copying and pasting file

To copy a file/folder, select the desired file/folder in the specified bucket/path and click Copy in More at the top of the UI. Alternatively, you can right-click it and select Copy. After the file/folder is successfully copied, you can paste it to another bucket or path. You can copy and paste multiple files/folders in batches.

Note：

If the name of the file/folder to paste already exists in the destination path, the old file/folder will be overwritten by default.

12. Renaming file

Select a file you want to rename, right-click, and select Rename. Alternatively, you can click Rename in More Actions on the right of the file. Then, enter your file name, and click OK.

Note：

Folders cannot be renamed.

13. Creating folder

To create a folder in the specified bucket or path, click Create Folder in the UI, or right-click in the UI and select Create Folder, enter the folder name, and click OK.

Note：

• The folder name can contain up to 255 characters, including digits, letters, and visible characters.
• The folder name cannot contain special characters such as \ / : * ? " | < >.
• .. cannot be used as the folder name.
• The folder cannot be renamed.

14. Viewing file details

To view the details of a file, click its filename or right-click it and select Detail. File details include filename, file size, modification time, access permission, storage class, ETag, headers, endpoint, object location, and an option to create a temporary object URL.

15. Generating file URL

Each file stored in COS can be accessed through a specific URL. If a file is private-read, you can request a temporary signature to generate a temporary access URL with a certain validity period.

You can generate a file URL in the following ways:

• In the list view, click the Share icon on the right of the object to generate a URL and copy it. If the file is public-read, the URL will not carry a signature and be valid permanently. If the file is private-read, the URL will carry a signature and be valid for 2 hours.

• Right-click a file and select Copy Link to generate a URL and copy it. If the file is public-read, the URL will not carry a signature and be valid permanently. If the file is private-read, the URL will carry a signature and be valid for 2 hours.

• On the file detail page, click Create link with expires to set the temporary URL, URL type, and validity period for the specified endpoint (available only when a CDN acceleration endpoint is enabled).

  

16. Sharing file/folder

Click Share in the operation column or the context menu to share a COS folder. You can also set a validity time for the link.

Note：

• You can only share a single folder but not multiple files.
• If multiple users share a folder, the file content may be hard to manage. In this case, you are advised to enable versioning for your bucket so that you can roll back to the desired historical version.

Parameter	Description
Permission	Sets the access permission for the shared folder.
- Can view	Pulls the folder list and downloads files in the folder using the access URL.
- Can edit	Pulls the folder list and downloads files in the folder, upload files to the folder, and create folders using the access URL.
Validity Period	In minutes, hours, or days If you log in to the client using a key, the validity period can be 1 minute to 2 hours for the root account, and 1 minute to 1.5 days for sub-accounts. If you log in to the client using a Tencent Cloud account, the longest validity period is 2 hours. The default value is the longest validity period allowed for the current user.
Password	A 6-character password automatically generated by the system. You can customize one as needed (numbers, letters, and symbols are supported).

Note：

When the link is valid, users receiving the link and password can access the folder.

17. Previewing file

COSBrowser allows you to preview media files, including images, videos, and audio. To preview a media file, double-click it or right-click it and select Preview or Playback in the context menu. On the file preview or playback screen, you can click:

• Copy Link to generate a file access URL and copy it.
• Download to download the file to the local file system. If a file with the same name already exists in the local file system, it will be overwritten by default.
• View on Mobile to generate a QR code for the file, which can be scanned on a mobile phone for direct view.

Note：

• Preview is available for images in most formats, .mp4 and .webm videos, and .mp3. and .wav audios.
• Please note that file preview will incur downstream traffic.

18. Searching for file

To search for a file, enter the filename in the search box at the top right of the bucket. COSBrowser supports prefix search and fuzzy search.

19. Searching for bucket

To quickly locate a bucket, enter the bucket name in the search box above the bucket list on the left.

20. Viewing historical versions or incomplete multipart uploads

• If versioning is enabled for your bucket, you can click View > Multiversion list above the file list to view the historical versions. Prefix search and clearing all historical versions (retaining the latest version only) are supported.

  

• If you pause or cancel an ongoing upload, incomplete multipart uploads may be generated. You can click View > Incomplete Multipart Uploads above the file list to view them. Prefix search and clearing all incomplete multipart uploads are supported.
  

Settings

System Feature	Description	Directions
Setting up proxy	COSBrowser uses the system-configured proxy to connect to the Internet. Please make sure that your proxy is set up properly or disable the proxy configuration if it fails to connect to the Internet.	1. Select Settings > Proxy. 2. Set up a proxy to connect to the Internet.
Setting the number of concurrent transfers	COSBrowser supports uploading/downloading multiple files in batches.	1. Select Settings > Download/Upload. 2. Set the number of concurrent transfers, which is 5 by default.
Setting the number of parts to transfer	COSBrowser supports uploading/downloading a file in multiple parts. When the file to be transferred exceeds a certain size, multipart transfer will be performed by default.	1. Select Setting > Download/Upload. 2. Set the number of concurrent parts to be transferred, which is 5 by default.
Setting the number of retries upon transfer failure	COSBrowser will retry failed tasks by default when transferring files.	1. Select Settings > Download/Upload. 2. Set the number of retries upon transfer failure, which is 5 by default.
Setting upload check	COSBrowser supports checking files online after upload to verify whether their size and status are correct.	1. Select Settings > Upload. 2. Select "Upload Check".
Limiting single-thread speed	COSBrowser supports limiting the upload and download speeds for a single thread. Total upload (download) speed limit = Single-thread upload (download) speed limit x Number of concurrent files x Number of concurrent parts	1. Select Settings> Upload/Download. 2. Set the single-thread upload/download speed limit, in MB/s.
Viewing local log	COSBrowser will record all the performed operations in the `cosbrowser.log` local file.	1. Select Settings > About. 2. Click Local Log and the system will open the directory where the local log is stored.