Encrypt, Decrypt, Digitally Sign and Protect Excel Files using Aspose.Cells Cloud API

Protecting and un‑protecting Excel files

What is “protect” in Aspose.Cells Cloud?
The Protect operation secures an Excel workbook by applying a password that restricts opening, editing, or modifying the file’s structure. The API also supports encrypting the workbook, decrypting it, and adding a digital signature for tamper‑proof verification.

API reference

HTTP Method Endpoint Required query / body parameters Sample request body Typical responses
POST https://api.aspose.cloud/v3.0/cells/{fileName}/protect fileName (path), password (query) { "password": "MySecret123" } 200 OK – protection applied, 400 Bad Request, 401 Unauthorized, 500 Internal Server Error
POST https://api.aspose.cloud/v3.0/cells/{fileName}/unprotect fileName (path), password (query) N/A 200 OK – protection removed, error codes as above
POST https://api.aspose.cloud/v3.0/cells/{fileName}/encrypt fileName (path), password (query) N/A 200 OK – file encrypted
POST https://api.aspose.cloud/v3.0/cells/{fileName}/decrypt fileName (path), password (query) N/A 200 OK – file decrypted
POST https://api.aspose.cloud/v3.0/cells/{fileName}/sign fileName (path) { "certificatePath": "/certs/mycert.pfx", "certificatePassword": "certPass" } 200 OK – digital signature added

Code example (C#)

using Aspose.Cells.Cloud.SDK.Api;
using Aspose.Cells.Cloud.SDK.Model.Requests;

// Initialise the API client
var config = new Configuration
{
    AppSid = "YOUR_APP_SID",
    AppKey = "YOUR_APP_KEY",
    BaseUrl = "https://api.aspose.cloud"
};
var api = new CellsApi(config);

// Protect the workbook
var protectRequest = new PostProtectWorkbookRequest(
    name: "Sample.xlsx",
    password: "MySecret123"
);
api.PostProtectWorkbook(protectRequest);

Prerequisites

  • An active Aspose.Cells Cloud subscription.
  • AppSid and AppKey for authentication.

Authentication
All requests must include the Authorization header with a valid JWT token obtained from the Aspose Cloud authentication endpoint.

Error handling
Check the HTTP status code and the Error object returned in the response body. Common errors include invalid password (400), missing file (404), and authentication failures (401).

Notes

Merge and Split Excel Files Convert Workbook Options