My phone will show full coverage and 3G but wont connect to anything requiring it. Voice will work fine but data wont work
Rebooting will fix the problem until the next day and I will have to reboot again.
A quicker way maybe to turn Airplane mode on for about 10 seconds then back off. You'll see it say searching and then after the bars show up, 3G shows up right after. It's quicker than a reboot and works for me I have this issue also from time to time but not daily like you.
The warehouse I work in has a few low signal areas and it seems if I spend a few hours in these areas, I lose the ability to use data even though "3G" is showing on the status bar. It doesn't happen all the time but like the above poster stated, all I have to do is switch into "Airplane" mode for a few secs and everything will work again. I'm wondering if there is some kinda power save mode built into the software that turns off data when signal is low for a longer period of time.