iPhone and wifi - no 'renew lease' button

JustLikeThat

I changed my router and set up wifi a couple of weeks ago and today got a message on laptop and desktop that there was a conflict withIP addresses. I dismissed the boxes and all continued ok. I later found that the iPhone would no longer connect (my iPad was ok).
In researching the problem I am convinced that I need to renew the lease under settings which would then have the router assign a new IP address etc thus also solving a probable cause of conflict as per this morning's message.
However! I no longer have a 'renew lease' button to press. How do I get it back? Apart from turning settings and the iPhone on and off, the only other thing I did was to 'forget the network' and then find it again etc.
I have a 3GS with 5.1.1 os.

Figment

Is iPhone set to use a static or DHCP IP address?

JustLikeThat

It's set on DHCP as it has been when working up until today. Same setting as working iPad. I tried moving to Static, but there was no improvement.

agrinnall

Have you restarted the router? I used to have a similar problem on my Linux netbook and it usually get resolved when everything had to reconnect to the router with new IP adresses.

securityguy

JustLikeThat wrote: »

It's set on DHCP as it has been when working up until today. Same setting as working iPad. I tried moving to Static, but there was no improvement.

Well if you allocate a new IP number which is on the same network, but outside the DHCP range, and it still doesn't work, then the problem isn't DHCP (assuming you've set up the gateway and the DNS servers correctly as well).

JustLikeThat

Thanks for responses. Having searches the internet about the problem for 4 hours straight, I am anxious to try to 'Renew Lease' to resolve the problem. If only that option appeared where it once was!
I could not find on the web any help to get it back as an option. When others have asked the question, answers have always reverted back to other solutions to the connection problem.
Some report that the option 'Forget this Network' has also disappeared, but in my case that is still there and I have tried that possible fix.
So, how do I restore the 'Renew Lease' option?

suki1964

Would resetting the phone not bring it back?

Lum

Rebooting the iPhone should make it get a new DHCP lease.

wongataa

Is DHCP correctly set up on the router?

JustLikeThat

I think the router is set up ok. My desktop is attached by ethernet and up until a few days ago, my laptop, iPad and iPhone have all been functioning by wifi without problem. I am reasonably confident that I need to press 'Renew Lease' on the iPhone so it gets a new IP address allocated to it. If only the 'Renew Lease' option hadn't disappeared!
I went to another home today where I was able to use their wifi with it. The 'renew Lease' option was also present there. It has disappeared since returning home, so it is a catch 22 situation. I assume i can find a way to reallocate a new IP address to the iphone another way, but I am anxious about fiddling with settings on the router and so messing up wifi to everything else.

JustLikeThat

Success! Thanks for responses, but no longer worry! I again tried 'Forget this network' but this time rebooted afterwards. When I enetered the password it started working again.