Hello. Had version zdesktop_1_0_build_1482_win32.exe installed and running on Windows XP machine. Received notification that an upgrade was available. Agreed to install (version zdesktop_1_0_build_1513_win32). The process uninstalled the existing version, but when it tried to install new update Java threw an exception about something being locked and the process failed. This left me with no Zimbra desktop installed.
I know this is more a Java problem than a Zimbra problem, but I can just see the effect this would have if several hundred zdesktop users suddenly had their e-mail disappear!