What about changing the Power Saving setting to either Intermediate or Off? Connectivity -> Connections -> select your WiFi connection then Edit -> Next, Next, Next, Advanced -> "Other" tab -> Power Saving If this works, it means your access point is not compatible with Power Saving Mode (PSM) and you might want to upgrade to the latest access point firmware in case that fixes it, or buy a replacement that does support PSM. Disabling or reducing PSM to "Intermediate" will result in worse battery lifetime on your N800. Also when discussing WiFi problems it's always beneficial to state your access point make/model/firmware.