HTC 8S problems with outlook syncing after being connected to WiFi

[Boddomend]

My HTC 8S stops syncing with an error message and it seems to happen after the phone has been connected to WiFi and then disconnected. For example if I am at home and connected to WiFi incoming emails appear on phone as they arrive at server. When I leave home and open an email account it advises the last time it synced was xx amount of minutes ago which coincides with the time it was last connected via WiFi. Attempting a manual sync gets an error message. The only resolution seems to be to switch on and off airplane mode. This applies to both my outlook accounts on my phone which are set to sync when items arrive. I suspect this is a bug anybody else experienced this?