Large file transfers performed using WebDAV continually restart and never complete


THE INFORMATION IN THIS ARTICLE APPLIES TO:

  • CuteFTP, version 9
  • EFT Server, all versions that support WebDAV

SYMPTOM

Large file transfers performed using CuteFTP's Web Distributed Authoring and Versioning (WebDAV) (HTTPS) connection continually restart and never complete.

RESOLUTION

Apply the Microsoft Hotfix available at http://support.microsoft.com/?id=2634328.

MORE INFORMATION

When posting data to an IIS 7.0 or 7.5 server over SSL, the server stops accepting data and the connection eventually times out and is reset by the server. This happens when the client sends enough data and is using a block cipher encryption algorithm. HTTP.SYS does not correctly account for data associated with the zero length padding messages used by certain CBC implementations. Once a buffer maximum is reached, HTTP.SYS stops accepting data on the connection.