gac, that's fine. My home network is 3600 seconds and work is set to 7200 seconds, although we are about to increase our computer numbers so that will change to ease the load on the network chatter. But no doubt Matt will connect up and come back to us for assessment.

As said, what are you on about?

Unless you have hundreds of devices connected, why on earth such a short lease time?

I would say the OP's original problem has bugger all to do with network settings, he more than likely has some malware.

Download, install and run malwarbytes etc and report back how you get on.

Exactly my thought. Have seen similar to this before.

Before running malware bytes though - run RKILL

Will terminate most malware processes that attempt to stop AV scanners running.

Also check that you've not had some obscure proxy set in your internet settings.

And throw in TDSKiller and Combofix to boot

I'm sorry guys I have confused you. Ignore me if you wish. I have no problem with that. But I'm more certain than ever it's a dhcp problem for Matt, but it will depend to an extent on how he connects (or not at the moment it seems!). To answer a question...my dhcp lease time at home on my router is set by default by Virgin Media for 3600 seconds (1hr). Most poeple will find they have short leases if they look. I don't need to change it at the moment. It's what all superhubs are set to by VM who are my isp. At least all the ones I've worked on have been set to that setting and it's largely irrelevant for most people. My network at work is set for twice that time as it's a small...ish network. If you have a large network then a bigger time is recommended as it cuts down on network chatter which slows the network, not the other way round Softscoop. My network however has specialised needs and shorter leases generally are in keeping with those needs. The 20 mins I've been talking about (and clearly some of you have not heard about probable due to better technology now) is the time a dynamic lease will take to expire if dhcp is not enabled on the computer and it has a dynamic connection. This can apply to usb modems which many of our staff run from home on a Tiscali/Talk talk deal and which incidentally, were still being dished out to us and other customers GAC in 2007 and later, so don't know where you get that 90's thing. Other isp's were doing it too in 2007/8 so it's still a current but outdated technology. I've never seen malware cause this on any computer yet myself. But it could be of course some malware. I spoke to IT support this morning and the first thing they said was same as me, dhcp is probably the cause because of the 20 min thing. Yes, it could all be wrong I know but I don't reckon it will be. Just my thoughts which you are free to ignore as I said and is as valid in my book as the suggestions you are all making. So all we need it Matt now!

I'm sorry guys I have confused you. Ignore me if you wish. I have no problem with that. But I'm more certain than ever it's a dhcp problem for Matt, but it will depend to an extent on how he connects (or not at the moment it seems!). To answer a question...my dhcp lease time at home on my router is set by default by Virgin Media for 3600 seconds (1hr). Most poeple will find they have short leases if they look. I don't need to change it at the moment. It's what all superhubs are set to by VM who are my isp. At least all the ones I've worked on have been set to that setting and it's largely irrelevant for most people. My network at work is set for twice that time as it's a small...ish network. If you have a large network then a bigger time is recommended as it cuts down on network chatter which slows the network, not the other way round Softscoop. My network however has specialised needs and shorter leases generally are in keeping with those needs. The 20 mins I've been talking about (and clearly some of you have not heard about probable due to better technology now) is the time a dynamic lease will take to expire if dhcp is not enabled on the computer and it has a dynamic connection. This can apply to usb modems which many of our staff run from home on a Tiscali/Talk talk deal and which incidentally, were still being dished out to us and other customers GAC in 2007 and later, so don't know where you get that 90's thing. Other isp's were doing it too in 2007/8 so it's still a current but outdated technology. I've never seen malware cause this on any computer yet myself. But it could be of course some malware. I spoke to IT support this morning and the first thing they said was same as me, dhcp is probably the cause because of the 20 min thing. Yes, it could all be wrong I know but I don't reckon it will be. Just my thoughts which you are free to ignore as I said and is as valid in my book as the suggestions you are all making. So all we need it Matt now!

The part that makes no sense (to me, at least) is your 20 minute thing. If a client isn't DHCP enabled, then there is no such thing as an initial 20 minute lease. It's either DHCP (in which case it will just broadcast for a new lease after whatever the lease time is), or it's not DHCP in which case it won't have leased in the first place and would need to have a correctly configured static IP address in order to work at all. I'm not aware of any implementation of DHCP which will lease for a bit, and then just not bother.

If I really stretch it, it sounds like what might actually be talking about is a 20 minute break on the ISP side between changing modems and such like, where you have to leave your ISP line with no device on it in order for the ISP to "forget" the old device and then you plug a new device in which will DHCP a new address. This certainly used to be the case with Virgin Media/NTL, if you changed modems for any reason you had to leave the line "open circuit" for a period of time otherwise your new modem would never get a WAN IP address. However since Matt heavily implies that restarting his laptop fixes the problem, which won't be touching the WAN side of his router, this can't be the problem.

Also, if I had a large network, there are arguments both for and against long lease times.

For:

- long lease time = you'll have the same IP for a while, making a particular computer easier to locate

- cuts down on DHCP traffic (although this is tiny, and I refuse to believe it could cause a genuine speed issue for any post-2000 LAN)

Against:

- if you have lots of devices and a small subnet, you could exhaust the pool due to leases not being re-used by the server quickly enough (i.e. if a client shuts down without explicitly releasing its IP, it won't get handed out by the server until the max lease time has expired)

So each case should be approached uniquely, without generalising into "large network = long lease times", your comments about network chatter slowing your network also make me think that you're probably not an appropriate participant in this particular discussion...

So each case should be approached uniquely, without generalising into "large network = long lease times", your comments about network chatter slowing your network also make me think that you're probably not an appropriate participant in this particular discussion...

Interesting comments Gac, but it's what the network is being used for too that counts. I work in a very specialised environment that is affected by such things. I am trying to offer help to Matt, unlike some who seem to be offering no suggestions of their own at all other than to debase anything I say. Which is fine of course if they actually believe what they are saying, as I do. Anyone who knows me also knows that if I'm wrong, I always say I'm wrong. I don't have a problem with that. Let's wait and see. Off to work now...my network needs me.

Edited 17 July, 201213 yr by Estate Man

Yes, I'm debasing everything you say. Giving crap advice is often worse than giving no advice at all, at least we're not all sending the guy off on a wild goose chase changing heaven knows what, and more than likely making the problem worse. Just because you believe what you're saying doesn't make you correct, and doesn't mean it's the solution. You're right of course in that no one knows anything until he comes back, but I think the chances of him actually making it back onto Briskoda have been greatly reduced by your posts, so I won't hold my breath...

Forgot I'd posted this as been working away! I'll have a good read tonight and post some results up.

Out of curiosity I've just started to have a problem with a phone and it's being looked at by bt. It's basically the phone isn't ringing but can take and make calls. I believe it to be a faulty filter and\or phone. It's also intermittent, would this cause any issues?

Easiest way to check.

Unplug the phone and filter completely, just leaving the BB equipment.

Browse for 20 min, see if it happens.

Filters can cause all sorts of weirdness. If you're having phone problems, it's also worth getting a corded phone and doing BT's quiet line test on 17070. If there's anything other than total silence (i.e. any crackling/hissing) then you can get BT to investigate as a voice fault, which will dodge any technician fees, and obviously if the copper is getting flaky then this can also improve your broadband connection without having to pay. Whereas your ISP will probably want to charge you a fee to get a broadband problem looked at. If you see what I mean.

Yes, I'm debasing everything you say. Giving crap advice is often worse than giving no advice at all, at least we're not all sending the guy off on a wild goose chase changing heaven knows what, and more than likely making the problem worse. Just because you believe what you're saying doesn't make you correct, and doesn't mean it's the solution. You're right of course in that no one knows anything until he comes back, but I think the chances of him actually making it back onto Briskoda have been greatly reduced by your posts, so I won't hold my breath...

You're unbelieveable! and very rude. My advice won't make any difference if it's not dhcp...it's easy to check and is proveable if I'm right. Which as I say may not be the case particularly in view of Matts last post. Some people are so up themselves Gac. You seem to like starting peeing constests. Anyhoo...have a nice evening and calm down.

Matt, I concur with Softscoops advice. That's a good test. Good luck.

How'd you get on with this?