FTP Grinds to a halt

Occasionally I need to use SmartFTP to backup all the pages on a web site - several thousand in total. Once a certain number of files have been transferred, SmartFTP grinds to a halt. The log display changes from coloured entries to all black text and the log entries rotate through a set of about 10 lines. The only action appears to be to halt the current transfer, close SmartFTP and restart it. It will then continue quite happily until that certain total of files or megabytes is reached again, at which point I have to stop the transfer and restart SmartFTP.

The version information for SmartFTP is
+- System -----------------------------
Microsoft Windows 2000 Professional
Service Pack 4 (Build 2195)

CPU Speed : 2009 MHz
Total Memory : 1535 MB
Free Memory : 881 MB

+- SmartFTP ---------------------------
Version : 2.5.1008.21
Time Stamp : 2007-12-05 00:19:47
Platform : x86

+- Application DLL --------------------
sfFTPLib.dll : 1.5.11.16
sfFavorites.dll : 1.0.4.21
sfFavoritesShellExtension.dll : 1.0.1.4
sfTransferQueue.dll : 1.0.1.21
SmartHook.dll : 1.0.2.2

+- Language ---------------------------
SmartFTP.exe : 2.5.1008.21

+- Internet Explorer ------------------
Version : 6.0.2800.1106

+- Winsock ----------------------------
Winsock : 2.2

Is there a solution to this problem other than stopping and restarting SmartFTP?

Richard Williams