Why am I receiving an error "The File is too large for the destination file system" when trying to upload a PHP file?

Environment:

Windows Vista/7 x64

Resolution:

64 bit versions of Windows Vista implement a core WebDAV driver that has been shown to be incompatible with our servers. This results in failures attempting to upload files. It will be necessary to obtain a third party WebDAV client in order to allow your system to connect correctly to our servers. The following link provides information on products you may consider:

http://www.webdrive.com/products/webdrive/WebDAVClient.html

Notes:

For more information refer to the following resources:

Overview of your WebDAV options by OS/Vendor 

Configuring WebDAV connection to access the Customer Portal