Hi jimmyn yes I agree with you, I can watch an iOS device try to connect, it gets a DHCP lease for a second and then drops it. Like you I have an SBS 2011 box, is yours also serving DHCP?

yes it is serving DHCP. I spent ages trying to work it out, but I think it is a fault with the router. I will contact Draytek today about this

I've got a ticket raised with Draytek - I'll let you know if there's a resolution to this problem

Thanks jimmyn, I have a ticket open also, hope they issue a firmware update or fix for this, have a loan AP-700 in place at the moment but I don't want to give it away to fix a problem which shouldn't exist.

We have a Vigor 2820 router set to DHCP using a D-Link DWL-2100AP. IPs are assigned fine to Windows laptops and used to be assigned fine to iPhone 4, but since upgrading to iPhone 5s and iPads often get the symptoms mentioned, ie. an IP is briefly given to the iOS device but then the device fails to connect. Restarting the router tends to get everything working again for a day or so, but then the problem returns. Doesn't therefore appear that this is a problem with the wireless part of the router, but with the core DHCP. Am thinking of swapping router but not sure whether to risk another Draytek or use another make, but like the ease of setting up VPNs with the Draytek.

Exactly the same problem! Nightmare