Friday, 23 February 2007

Newsletter Issue 127, February 2007

Sam Young Newsletter

Issue 127, February 2007
Hi guys,
Think about how you keep your backups. Read on in CD & DVD Longevity below.
Learn a great new tip in Auto Filter Subtotal in Excel
Don't forget, if you want to be taken off my mailing list, click here to send me a reply e-mail and I will remove your name.

CD & DVD Longevity

A few years ago I found an interesting article in the Dutch magazine, PC Active, on the longevity of CD-Rs. I reported their findings on some tests they ran on CD-Rs in Newsletter 69. PC Active's article is viewable, translated, here online (unfortunately the original article & their test data appears to have been taken down).
However, I was reading another e-newsletter recently, and the issue has come up again for burned CDs and DVDs (ie, home-recorded, not commercially produced, pre-recorded CDs and DVDs, such as those you buy at music or movie shops).
Commercially produced CDs and DVDs have very long lifespans. They're mainly vulnerable to physical damage to the readable surfaces of the discs, so keep them clean, protected and out of temperature fluctuations as much as possible and they should be fine for years.
The goss on the street is that some CDs/DVDs only last for a couple years, particularly if they're exposed to direct sunlight, or if they are covered with DIY sticky labels (the ultraviolet in sunlight and sticky label adhesive can react with and destroy the layer of dye that carries your data).
In reality, no one really knows how many years home-recorded discs will last, because burnable CDs and DVDs haven't been around long enough. The studies you see on the life expectancy of CDs  are based on accelerated-aging tests, which are really just a form of educated guess.
Basically you need to ensure that you store your burned CDs and DVDs in a cool, dark place, well protected from each other and don't handle them too often. Make two copies of really important stuff, on better quality media. But if you are using CD-Rs for regular data backups, use them as cheap as you like (because they won't have to last for 100 years)... or for backups use three rotating CD-RWs and check that they are legible regularly (run a scandisk on them).
There is some independent longevity information on CDs and DVDs which has been running online for nine years at CDR FAQ (go to Andy McFadden's CD-Recordable FAQ). It's updated frequently with new information.
But, wait, there's more. Fred Langa, of LangaList fame, says "If that's too much data to wade through, then "Is Your Data Disappearing?" may be more to your liking. It's an article I wrote for InformationWeek that boils down McFadden's FAQ and numerous other info sources to focus solely on the question of the lifespan of recordable media, including the various types and brands of CDs."
Auto Filter Subtotal in Excel

If you have the Auto Filter on in Excel, and if you click the toolbar Sum button in a cell on one of the columns, you have probably noticed that the formula appears in the cell as 'SUBTOTAL' instead of 'SUM'.
Because the SUBTOTAL function uses only the visible cells, ignoring all the hidden rows, when you use the Auto Filter to filter your data, your sum adjusts to add up only those rows still visible. The subtotal formula will read eg "=SUBTOTAL(9,A1:A100)". However, if all the rows in A1:A100 are visible it will simply SUM them all and give the same result as =SUM(A1:A100).
Note that '9' in the brackets on the subtotal function. The subtotal only happens because of that magic number.
Aside from the 9 being subtotal, Excel uses the numbers between 1 and 11 to supply a function's first argument, and each number does something quite different, and very useful.
For example;
  • 2 COUNT
  • 3 COUNTA
  • 4 MAX
  • 5 MIN
  • 7 STDEV
  • 8 STDEVP
  • 9 SUM
  • 10 VAR
  • 11 VARP
But wait, there's more. As you only need to use a number between 1 and 11, you can make one SUBTOTAL function perform a function of your choice. You can even make the choice from a drop-down list anywhere on your Excel spreadsheet.
Very handy!

Missing Shell.dll

If, when installing software on an XP PC, you get a dialog box that says you are 'Missing SHELL.DLL', first you need to find out why Shell.dll disappeared.
There is a fairly common browser hijacker that can cause this problem, usually adding "Home Search Assistant," "Shopping Wizard," and "Search Extender" to your system, and may also reset your browser's home page so that a popup appears at every start.
If you do have this malware on your system, repairing Shell.dll won't work because the malware will simply corrupt your new copy.
So first, run your favourite anti-malware tools to make sure your system is squeaky clean and free of all malware (major test labs currently rate Webroot's Spy Sweeper and PC Tools' Spyware Doctor as the best antispyware products).
If "Home Search Assistance" and its related friends are, in fact, causing your problem, the free AboutBuster utility can remove them.
Once you're sure your system is clean, you can download a fresh copy of Shell.dll from any number of online sources., for example, has a good Shell.dll page. Copy the DLL file into your DLLcache folder (usually found at C:\Windows\System32\DLLcache). Then re-register the DLL this way:
  • Click Start, Run.
  • In the Run dialog box, enter (change C:\Windows to the correct location on your system): regsvr32 - C:\Windows\System32\DLLcache\Shell.dll
  • Click OK.
  • Reboot, and your Shell.dll problems should be fixed!
By the way, the above steps can resolve a huge number of problems with other missing/corrupted DLLs. Just use the example above as a template, downloading whatever DLL you need and substituting its name in the regsvr32 command.

TLAs for SMEs

Here are this newsletter's TLAs for you:
  • VCSEL, Vertical Cavity Surface Emitting Laser. A specialised laser diode that apparently promises to revolutionise fibre optic communications by improving efficiency and increasing data speed. Pronounced 'vixel.'

Please feel free to email me with any TLAs that you want to get the bottom (meaning!) of.

Tips, Short+Hot Keys
Here's a few simple tips on opening Windows Explorer quickly:
  • Launch Windows Explorer: using the Windows key (the key with the Windows logo on it) - WindowsKey+E
  • Launch Windows Explorer: right click on the Start button, select Explore from the pop-up menu
  • Opening Windows Explorer in a specific folder: navigate to the folder in Windows Explorer, then click and hold on the folder icon that appears at the left-hand end of the title bar of the window, drag and drop the folder icon on your desktop to create a shortcut.

Hot Linx
You can view photos of anywhere in the world - usually taken by locals - at Woophy. Go to
Well, the vegetarians definitely have an edge in the IQ stakes, as do people who don't eat red meat. Read on at
And if you want to know how many calories you are burning doing exercise, this site is quite handy at
The trials & tribulations of mixed breed dogs vs pedigrees can be read about at

                                Catch you again soon!! E-mail your suggestions to me here

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