I'm new to Android phones but my brother has had some for a couple years now and he has no idea what's causing this problem. I have a Samsung Gio and I use both gmail and normal mail (pop3 for business). What happens is if I go into my inbox right now on my phone, it does not list any emails, despite having lots in my outlook inbox. If I send myself an email (or anyone does from anywhere) and I get it first on my phone (as opposed to checking it on my outlook) it WILL show up on my phone. However as soon as I check it/receive it on outlook, it will disappear on my phone. Works the same way in that if I receive it first on outlook, it never will show up on my phone. I thought that maybe this is just a problem with the stock email app, but I downloaded K-9 mail and it does the exact same thing. I have been through every option I can find and nothing will fix it. As such, my gmail never does this and will load all the emails I have in my inbox. Any help would be greatly appreciated.