Requirements . v5.1

What you need before installation.

Framework

ASP.NET Web Forms on .NET Framework 4.8 (or higher). Same baseline as 5.0.

Browsers

Evergreen Chrome, Edge, Firefox, Safari. Encryption + offline queue require a secure context (HTTPS) for SubtleCrypto and service workers.

Hosting

IIS Express, IIS, or any ASP.NET host with integrated pipeline mode. Reverse proxies must not strip the Service-Worker-Allowed header if you use offline mode.

Storage

Write access to App_Data\UploaderTemp. For direct-to-cloud transports, register a signer (S3 / Azure / GCS) instead.

Core stack

For ASP.NET Core, use CoreUpload.

The quick-start notes bundled with the local AjaxUploader demo explicitly point ASP.NET Core teams to CoreUpload instead of this Web Forms control.