From WinAgents Software Group:
A standard TFTP command-line utility possesses a number of serious drawbacks. It does not support important features such as blocksize option, and is unable to transfer files larger than 33 MB. As a result, the standard TFTP client is often not very useful at all. WinAgents Software Group has developed a freeware replacement for the standard TFTP client application that supports all necessary features. You can download it now from our site.
Key features of WinAgents TFTP Client for Windows:
Platform: Any 32-bit Windows platform except WinCE;
Fully compatible with RFC1350, RFC2347, RFC2348 and RFC2349;
Supports the transfer of large files;
Supports 'tsize', 'blocksize' and 'timeout' TFTP options.