Symptoms

After a file is downloaded to the activeEcho client on a Windows XP or Windows 2003 computer it is uploaded again, in some cases multiple times, creating a new revision each time.

Reproduction steps

1. Connect to a Windows XP or Windows 2003 activEcho client to the activEcho server.
2. Log in to your activEcho server and upload a file to the server using the web interface.
3. Wait until the file is downloaded to the Windows XP or Windows 2003 computer running the client.

Cause

This is caused by Windows Security Essentials.  On Windows XP and Windows 2003, the Windows Defender component of Windows Security Essentials scans files in the system and overwrites data in the file.  The activEcho client and other tools can't differentiate this change from legitimate data updates in the file system monitoring service.

Solution

This only occurs on Windows XP and Windows 2003.  Excluding the activEcho folder from the real-time download scanning in Windows Defender should eliminate or at least alleviate this problem.