Hello,

You can use X509Certificate2(Byte[], String) to read the certifcate to byte[] like following code.

By the way, please make sure this build action of certificate.pfx is MauiAsset

  public async Task<byte[]> ReadCertificateAsByteArray()
           // Get the stream of the certificate from the Assets folder
           using (var stream = await FileSystem.OpenAppPackageFileAsync("certificate.pfx"))
               if (stream != null)
                   using (var memoryStream = new MemoryStream())
                       // Copy the stream to a MemoryStream
                       stream.CopyTo(memoryStream);
                      // Convert the MemoryStream to byte[]
                       return memoryStream.ToArray();
                   Console.WriteLine("Certificate file not found in the Assets folder.");
       catch (Exception ex)
           Console.WriteLine($"Error reading certificate: {ex.Message}");
      return null;
Then, you can use it in X509Certificate2 like following code.
  var certAsByte = await ReadCertificateAsByteArray();
  var cert = new X509Certificate2(certAsByte, "password");
Best Regards,
Leon Lu
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