**Originated From:** [https://products.aspose.app/slides/merger/navigation/uploaded/uploaded/uploaded/errorReportForm/errorReportSuccess/errorReportForm](https://products.aspose.app/slides/merger/navigation/uploaded/uploaded/uploaded/errorReportForm/errorReportSuccess/errorReportForm)
**Exception:** Invalid file, please ensure that uploading correct file
{"isSuccess":false,"idError":"InvalidFile","message":"Unknown file format."} undefined
Error on zipping file System.NullReferenceException: Object reference not set to an instance of an object. at Aspose.Slides.Web.Core.Services.Storage.TemporaryFolder.SaveAsync(Stream stream, String fileName, CancellationToken token) in C:\JenkinsNode\workspace\Slides\Aspose.Slides.WebApps Premerge (.NET 5)\src\Aspose.Slides.Web.Core\Services\Storage\TemporaryFolder.cs:line 38 at Aspose.Slides.Web.Core.Services.Error2ForumService.<>c__DisplayClass6_0.<b__0>d.MoveNext() in C:\JenkinsNode\workspace\Slides\Aspose.Slides.WebApps Premerge (.NET 5)\src\Aspose.Slides.Web.Core\Services\Error2ForumService.cs:line 121 --- End of stack trace from previous location --- at Aspose.Slides.Web.Core.Services.Error2ForumService.PostAppToForums(Error2ForumRequest model, CancellationToken cancellationToken) in C:\JenkinsNode\workspace\Slides\Aspose.Slides.WebApps Premerge (.NET 5)\src\Aspose.Slides.Web.Core\Services\Error2ForumService.cs:line 115
Please share a problematic file and we’ll investigate this scenario.