Hey Nicole,
You are not alone on this. Mine does the exact same thing. I can do the factory reset, this will allow me to do setups and make changes. After 15/30 min of running, it will do the following:
1. Under load, using PPTP or IPSEC connections, it will reboot it's self.
2. If you are on-line gaming, it will begin to lag, then lockup and reboot it's self.
3. The web interface will lock up, by that I mean, you can log into it and view things like logs, or status, but if you try and make any configuration change it will hang, and reboot and not accept the change.
4. The time will reset back to 2004, and can not be fixed because of point 3.
They may have fixed the port forwarding issue, but there are still many issues that have not been addressed. Unfortunately this very expensive gaming router is really only capable of allowing you to connect to your ISP and surf the web, anything beyond that it will begin to lag and crash/reboot.
This router is in serous need of some development work to fix it to be usable in any situation other than surfing web pages.
Dlink tech support does not have the knowledge to help you, or any of us, which is very apparent if you read other threads in this forum. They will suggest fixes that the router is not even capable of, or have you make changes that don't even pertain to the issues you are having, we are alone...
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The only tech I have seen on the board that cares, and seems to know anything is Lycan, and I'm hoping that Lycan is reading this thread, and maybe passing these issues on to a development team for review.