one of my users used this WE the webmail to read her emails. After she switched to outlook (2010 32bits) she was then unable to get some of these new messages in her inbox. This only happens to half a dozen of emails which are still in zimbra inbox, but never download in outlook.

outlook : 14.0.6112.5000 32 bits
Zimbra Client : 6.0.6089.9
Zimbra Server : 6.1.10_GA_2692

how can we avoid such situation?