Upgrading Your Code to WebDAV Client Library for .NET v1.1
In the version 1.0, client-side buffering was turned off for file uploads. For best compatibility with any WebDAV servers now data is buffered on a client side by default. When migrating from version 1.0 make sure you increase the timeout before upload. You may also turn off buffering if you use Basic, Digest or Anonymous authentication.
See Uploading and Downloading Files for more details.