Monday, 3 November 2008

AVG causes web pages to fail

Had a fun time this afternoon diagnosing a problem on my father's WinXP laptop. He could send and recieve e-mails, and connect to secure (https://) websites, but not plain websites (http://). It looked like something was blocking port 80, but Windows firewall wasn't and there didn't seem to be any other firewall software installed.

He is using AVG AntiVirus, paid for, but not with the firewall component.

Eventually tracked it down to a process called avgnsx.exe which seems to be the thing that both LinkScanner and Web Shield use in their work. Turning off both these protections and suddenly we could browse the web again!

AVG have some comments, and a possible fix, on their FAQ pages:
http://www.avg.com/faq.num-1561#faq_1561

Interestingly, and perhaps related, we also saw repeated requests to reboot following AVG updates. This might be related to the above problem, and is also dealt with in the AVG FAQ:
http://www.avg.com/faq.num-1444#faq_1444

For those who are interested, I found out what was blocking port 80 by installing the excellent, and free, TcpView from Microsoft Windows Sysinternals:
http://technet.microsoft.com/en-us/sysinternals/bb897437.aspx

Run this with "Always on Top" selected, and see which processes do things when you try to navigate to a web page.

Search things: https not http, port 80 blocked, AVG, no firewall, many web pages not found.

Thursday, 9 October 2008

Two-part business site SEO

Well, the changes to Bell Leisure's site seem to have helped a great deal with their Google listings. The site is now split into two sub-domains, one for swimming pools and one for the snooker and pool tables half of their business.

This has also made it possible to list the two almost-separate businesses as separate items in Google's Local Business Centre. This means that Bell Leisure appears nicely for relevant searches for either part of their business.

However, even with the subdomains being listed separately, Google was still returning the "top level" page for searches. I've now moved the descriptive text from this page, and into the two sub-domains, in an attempt to make the subdomain home pages be listed first.

We'll see what happens!

Spamhaus bullies

Yesterday Spamhaus decided to block a whole 254 address range of IP addresses, owned by Netrino who host my server, because they didn't consider that Netrino had taken suitable action against a spammer.

Today they have relented a little, and only a 16 address range is now being blocked. So e-mail from hundreds of innocent businesses is now able to flow a little better again.

It would have been nice if Spamhaus had done a little more homework before blocking such a large range of addresses. The addresses clearly come from a server hosting company, with only a few IPs allocated to each of their customers.

At least it has prompted me to find out how to relay outbound e-mail via my other server, hosted by Clustered.net. This worked fine while it was needed, and I've updated all my customers' SPF records to allow either server to send out mail for their domains. MailScanner's watermarking also proved useful in this situation, as each message only needed to be scanned by one of the servers.

So while Spamhaus' bullying action certainly annoyed, it has resulted in a little more resilience against potential spam blacklisting for Fonant e-mail services if this sort of thing ever happens again.

Thanks Spamhaus!

Friday, 20 June 2008

Verified by Visa, Barclays style: zero additional security!

How secure is the additional protection provided by Barclays Bank's Verified by Visa system? Here's what I have to do if I've forgotten my VbV passphrase, which is needed to use my card to shop on-line:

Step one:

Step Two:


Step Three:

All done:


So the answer is: not very much at all. The only thing someone who has my card needs to find out is my date of birth, and with that they can then use my card for online purchases that are protected by Verified by Visa. They even get told my VbV username (blurred out in the image above), which allows them to log into my VbV account and see all my transaction history. Not good.

I particularly like the bit where it says "Your password will be used on all future purchases at participating online stores". What it really means is "You can forget your password, as you only need your card and your date of birth to set a new one", and this is, in fact, what I always do.

Tuesday, 10 June 2008

Reducing car fuel prices

You may have seen the lovely "pyramid" e-mail doing the rounds, telling you:
For the rest of this year DON'T purchase ANY petrol from the two biggest
oil companies (which now are one), ESSO and BP.

If they are not selling any petrol, they will be inclined to reduce
their prices. If they reduce their prices, the other companies will have
to follow suit. But to have an impact we need to reach literally
millions of Esso and BP petrol buyers. This is really simple to do!!

Sounds an excellent way to reduce the price of fuel, and perhaps almost anything else! However this doesn't stand up to much analysis.

Starting Point



As a starting point, we have this situation:
  • Petrol price around £1.20/litre
  • People buying petrol from their nearest or cheapest petrol station


Stage One complete


Assuming that car drivers in the UK boycott Esso and BP in their millions (perhaps chosing to run out of fuel rather than buy their petrol) we would, apparently, end up in this situation:

  • Very few people buying petrol from Esso or BP.
  • Normal petrol price £1.20/litre.
  • Price at Esso/BP reduced to 69p/litre to encourage people in.

So far so good, we've forced Esso/BP to reduce their petrol price. But we do have an awful lot of people who are now deliberately choosing to buy more expensive petrol than they could do.

The plan is that the other petrol stations will then reduce their prices to match Esso/BP. But of course there's no need for them to do so, as people are buying their petrol at the higher price already!

Stage Two complete


Anyway, assume that all petrol stations now charge 69p/litre. We all return to buying petrol at any garage. Guess what? The very next day all the garages will have put their prices back up again!

After all that effort, we have this situation:
  • Petrol price around £1.20/litre
  • People buying petrol from their nearest or cheapest petrol station


The Answer


What we are talking about is Market Forces, and they already work, assuming competition between petrol stations, to keep the price of petrol as low as is possible without making a loss (although I suspect supermarket stations do sell at a slight loss, to encourage people to shop for their food, clothing, etc. there too).

The only ways to reduce fuel prices in a Market economy are:

  • Reduce demand by getting everyone to buy less petrol and diesel.
  • Increase supply by finding a massive crude oil field with good quality and easy-to-extract oil in it. Or perhaps invade and take control of any countries that have (a) oil and (b) no nuclear weapons.

Even reducing tax would probably have little effect on prices, as the current situation shows that you can sell petrol and diesel at £1.30/litre without too much loss in business. A tax reduction would therefore result in increased profits for the oil companies.

Thursday, 5 June 2008

More Database madness

Another attempt to introduce the impossible National Identity Database by the back door:

http://www.theregister.co.uk/2008/06/04/government_database_volunteers/

And they wonder why no-one is willing to organise events on a voluntary basis if there are people under 18 involved...

I wonder if running a Dr. Bike bike checking session counts as "working with children"? How about leading a family cycle ride when the children's parents are present?

The requirement to pay £60+ for registration on this massive database, plus the new need for stupendous levels of public liability insurance, will kill off so many useful and pleasant activities for children to take part in.

It we don't bother asking our fantastic baby sitter to register, are we breaking the law? Does it matter whether she's a personal and trusted friend of ours?

Complete madness...

Tuesday, 27 May 2008

IE6, AlphaImageLoader, and links

I too have hit the problem where links, that are inside elements with (a) absolute positioning, and (b) a background image loaded using AlphaImageLoader, are unclickable. Yet another annoying IE6 bug!  The sooner that browser is dead, the better...

Anyway, I seem to have fixed the problem (thanks to others out there, especially Stu Nicholls and Drew McLellan, with their fix descriptions) by adding another div within the original absolute-position-and-semi-transparent-background div and to contain the link(s). This div has no use in other browsers, but in IE6 I apply the AlphaImageLoader background to that one, turning off the background-image on the original div. Since the AlphaImageLoader background is no longer applied to an absolutely-positioned element, all is well again, and links are clickable in IE6!

<div class="withbackground">
 <div>
  <a href="http://www.example.com">Link here<a>
 </div>
</div>

The normal style sheet has what you'd expect for absolute positioning and a semi-transparent PNG background image:

.withbackground {
 position: absolute;
 top: 10px;
 left: 20px;
 background-image: url(images/semi-transparent.png);
}

and then, in an IE6-only additional style sheet, we turn off the original PNG, and apply it using AlphaImageLoader to the child div, which isn't positioned:

.withbackground {
background-image: none;
}
.withbackground div {
filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='images/semi-transparent.png', sizingMethod='image');
}

and with all that in place, the page works in every decent browser, and also in IE6!

Wednesday, 21 May 2008

Eco-Eye Mini electricity consumption monitor

I have just had delivery of an Eco-Eye Mini electricity consumption monitor, and I'm very impressed.

The monitor is easy to install, just insert the batteries and clip the sensor wire around the live wire in your electricity meter cupboard. You then have a very clear read-out of your current electricity consumption in KW. You can enter the current price per unit for your electricity, and the monitor will then also be able to display the current cost per hour (or day, week, month, or year).

The monitor's output has a resolution of 10 watts, so you can see the effect of turning lights on and off, even low-energy ones.

The range of the monitor is reasonable. In our house with solid internal walls it works in most places apart from the furthest points from the transmitter. The range seems similar to that of our Speedtouch 585 v6 wireless router.

The Eco-Eye is made in the UK, and much more information about the unit is available from the manufacturer's web site: http://www.eco-eye.com

The unit is competitively priced too, and if you order from the Good Energy Shop soon you can get a 25% discount, making the monitor £33.94 including postage.

Later in the summer there should be a USB-interfacing receiver available too, with battery backup and data retention for when your computer is switched off. This listens to the same radio signals as the standard monitors, so will work nicely in parallel. Should make analysing trends in household electricity usage easy.

Wednesday, 9 April 2008

SEO for business with two sides

I've been looking into how best to optimise the search engine results position for a local company called Bell Leisure. They have two quite distinct sides to their business: one half is selling pool and snooker tables, and anything related, and the other half sells, installs, and maintains swimming pools and hot tubs.

Their current site is all under the single www.bell-leisure.com domain, with two sub-directories for the two halves of the business. The effect seems to be that their site is listed well in pool and snooker table categories, and also appears well in search results for these types of product. However the swimming pool side of the business doesn't appear well in search results, presumably because it doesn't fit within the categorisation of the site as a whole.

If the company agrees, I'm going to try splitting the site into two separate sub-domains, one for each distinct part of their business.

So http://www.bell-leisure.com/swimming will move to http://swimming.bell-leisure.com, and http://www.bell-leisure.com/tables will move to http://tables.bell-leisure.com. I'll leave the existing "home" page at http://www.bell-leisure.com, and will put in permanent re-directs for the other pages, so previously-created links will still work.

Local Post Office Closures

Following closure of many of the small local Post Offices here, we now have a terrible situation and dramatic loss in service. The central Post Office in Lancing is now always heavily congested, with long queues and waiting times even at off-peak times.

The net result is that what used to be a ten-minute job, to walk to the local Post Office to post a parcel, now takes more than an hour.

Yet another case of corporate profit taking precendence over public service.