I'd add restarting the modem into that as well, as it if "locks up" DNS number 
(which are normally being handed out via Bridge mode on the AIrport 
"generally") then it won't always solve the issue.
If you turn everything off. Then turn on the modem and wait about a minute. 
Then turn on the Airport Express. Wait another minute, then start connecting 
devices again.
This then "Refreshes" all the DNS settings and lets each machine grab another 
IP address.
The other work around (which is a bit more annoying if you go elsewhere 
sometimes) is to set the iPhone to have a Static IP address on your home 
network as well. When I can't be bothered resetting everything (or I'm too busy 
to) and my iPhone doesn't work, I just do this quickly. Then when I have time 
(hahaha yeh right), I then go back to switching it all off and on again later 
on). (Sunday job if it ever needs). 
Sometimes I can go months and months and months with no issues. Then it just 
happens. So I just flick it all off, and away I go again for a long time 
again…..

Hope that extra info helps.

Kind regards
Daniel
---
Daniel Kerr
MacWizardry

Phone: 0414 795 960
Email: <daniel AT macwizardry.com.au>
Web:   <http://www.macwizardry.com.au>


**For everything Apple**

On 26/02/2013, at 10:07 PM, Brian Risbey <[email protected]> wrote:

> Hi 
> This may relate to my enquiry about Airport Express wireless range issues I 
> was having - loss of network access but wireless network still showed up on 
> iPhone.
> It lead to $35 over-use mobile data bill last month - ouch!
> 
> I have restarted both the iPhone and the Airport Express.
> 
> Brian
> 
> 
> On 26/02/2013, at 7:44 PM, Daniel Kerr <[email protected]> wrote:
> 
> Unfortunately it can happen to all iOS's. DNS settings can "lock up". 
> Normally fixed via restarting the iPhone. Sometimes it actually involves 
> restarting the router as well. 
> 
> Kind regards
> Daniel
> 
> Sent from my iPhone 4s 
> 
> ---
> Daniel Kerr
> MacWizardry
> 
> Phone: 0414 795 960
> Email: <daniel AT macwizardry.com.au>
> Web: <http://www.macwizardry.com.au>
> 
> ** For Everything Apple **
> 
> On 26/02/2013, at 7:41 PM, Neil Houghton <[email protected]> wrote:
> 
>> Hi Peter,
>> 
>> No, I can't blame the upgrade - I was just about to do the upgrade and
>> wanted to limit it to the incremental rather than full download - so went to
>> do via the phone rather than iTunes - that was when I noticed the problem
>> (ie before initiating the upgrade).
>> 
>> I solved the wifi problem by following your reboot suggestion - then went
>> ahead with the upgrade to iOS6.1.2 (via wifi) I have now installed the
>> update and everything is still OK - touch wood ;o)
>> 
>> Cheers 
>> 
>> 
>> 
>> Neil
>> -- 
>> Neil R. Houghton
>> Albany, Western Australia
>> Tel: +61 8 9841 6063
>> Email: [email protected]
>> 
>> 
>> 
>> on 26/2/13 6:43 PM, Peter Crisp at [email protected] wrote:
>> 
>>> Ok, thanks for letting me know Neil. I have iOS 6.1.2 and I suspect the
>>> upgrade to that iOS was the source of the introduction of a bug under 
>>> certain
>>> circumstances.
>> 
>> I had never had the issue prior to upgrading to 6.1.2. What
>>> iOS do you have on your phone?
>> 
>> 
>> 
>> Regards
>> 
>> Pete
>> 
>> On 26/02/2013, at 6:27 PM,
>>> Neil Houghton <[email protected]> wrote:
>> 
>>> Hi Peter,
>>> 
>>> Thanks for that
>>> - yes that sorted the problem ;o))
>>> 
>>> 
>>> Cheers
>>> 
>>> 
>>> 
>>> Neil
>>> -- 
>>> Neil
>>> R. Houghton
>>> Albany, Western Australia
>>> Tel: +61 8 9841 6063
>>> Email:
>>> [email protected]
>>> 
>>> 
>>> on 26/2/13 4:45 PM, Peter Crisp at
>>> [email protected] wrote:
>>> 
>>>> Try rebooting the phone. I had this
>>> very issue my self two weeks ago and that
>>>> resolved it instantly.
>>> 
>>> I am
>>> curious if it works or not so please let me know
>>>> Neil.
>>> 
>>> Regards
>>> 
>>> 
>>> Pete
>>> 
>>> On 26/02/2013, at 12:36 PM, Neil Houghton
>>>> <[email protected]>
>>> wrote:
>>> 
>>>> Just to add:
>>>> 
>>>> € The iPhone was previously
>>>> connecting to
>>> the network OK
>>>> € I have now rebooted both the modem and the
>>>> Airport
>>> Extreme - but with the
>>>> same result - the iMac and iPad connect fine
>>>> -
>>> the iphone sees the network
>>>> but gives me a "incorrect password" dialogue
>>> 
>>>> 
>>>> 
>>>> on 26/2/13 11:56 AM, Neil Houghton at [email protected]
>>> wrote:
>>>> 
>>>> A strange problem here.
>>>>> 
>>>>> I picked up my iPhone, at
>>> home, and noticed
>>>> that it was not connected to my
>>>>> airport network.
>>> 
>>>>> The network is
>>>> working fine and my iMac and iPad are both connected
>>> and
>>>>> communicating just
>>>> fine.
>>>>> 
>>>>> I tried turning wifi off and then
>>> on again and the phone "sees"
>>>> the network
>>>>> but does not connect.
>>> 
>>>>> I even tried removing the network
>>>> from the remembered list (untick
>>> the
>>>>> remember this network box).
>>>>> 
>>>>> At
>>>> this point, with wifi
>>> turned back on:
>>>>> 
>>>>> € The phone "sees the network
>>>> € Selecting the
>>> network opens the password dialogue
>>>>> € Entering the password
>>>> gives me a
>>> "incorrect password" dialogue
>>>>> € I AM entering the CORRECT
>>>> password (I
>>> even checked the password in the
>>>>> keychain of the connected iMac
>>>> - to be
>>> sure!)
>>>>> 
>>>>> At this point I am at a bit of a loss as to how to
>>>> proceed
>>> - any ideas?
>>>>> 
>>>>> 
>>>>> Cheers
>>>>> 
>>>>> 
>>>>> Neil
>>>> 
>>>> -- 
>>>> Neil R.
>>> Houghton
>>>> Albany, Western Australia
>>>> Tel: +61 8 9841 6063
>>>> Email:
>>> [email protected]
>>>> 
>>>> 
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