Use ContentDispositionHeaderValue.

framework/src/Volo.Abp.AspNetCore.Mvc/Volo/Abp/AspNetCore/Mvc/ContentFormatters/RemoteStreamContentOutputFormatter.cs

@@ -28,8 +28,9 @@ namespace Volo.Abp.AspNetCore.Mvc.ContentFormatters
 
                 if (!remoteStream.FileName.IsNullOrWhiteSpace())
                 {
-                    //https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition#syntax
-                    context.HttpContext.Response.Headers.Add("Content-Disposition", $"attachment; filename=\"{remoteStream.FileName}\"; filename*=UTF-8''{Uri.EscapeDataString(remoteStream.FileName)}");
+                    var contentDisposition = new ContentDispositionHeaderValue("attachment");
+                    contentDisposition.SetHttpFileName(remoteStream.FileName);
+                    context.HttpContext.Response.Headers[HeaderNames.ContentDisposition] = contentDisposition.ToString();
                 }
 
                 using (var stream = remoteStream.GetStream())

framework/test/Volo.Abp.AspNetCore.Mvc.Tests/Volo/Abp/AspNetCore/Mvc/ContentFormatters/RemoteStreamContentTestController_Tests.cs

@@ -15,7 +15,7 @@ namespace Volo.Abp.AspNetCore.Mvc.ContentFormatters
         {
             var result = await GetResponseAsync("/api/remote-stream-content-test/download");
             result.Content.Headers.ContentType?.ToString().ShouldBe("application/rtf");
-            result.Content.Headers.ContentDisposition?.FileName.ShouldBe("\"download.rtf\"");
+            result.Content.Headers.ContentDisposition?.FileName.ShouldBe("download.rtf");
             (await result.Content.ReadAsStringAsync()).ShouldBe("DownloadAsync");
         }