DoubleClicks.info About Computers for Newbies & Everyone Else

December 12, 2017

Tunnels on the Internet

At a recent speaking engagement, I was talking to the group about security.  This discussion was centered on Virtual Private Networks or VPNs.  Since 1996 when a Microsoft employee created a secure tunneling system for computers, VPNs have been around.  It was not as we know a VPN today; however, it certainly set the process in motion.

Basically, a VPN is a “tunnel” through the internet that connects a specific group of computers.  This network keeps out anyone who does not have the proper keys to work with the others.  Businesses first started using VPNs to connect their data networks between different locations around the globe.

A VPN keeps out the bad guys, or not even bad but just people you do not want looking at your data.  In more recent times VPN usage has been encouraged for individuals too.  This statement may lead you to ask, “Why?”

The reason is security.

If you go into a local coffee shop and check your spam email you may be fine.  But if you have private email which you are sending and you do not want others to see, a VPN may be needed.

When you are in a coffee shop, or any public Wi-Fi for that matter, it is most likely an open connection.  That means anyone walking by can access the internet through that business’s network without a username or password.  They may even require usernames and passwords but you do not own that connection.  You do not know who else is there in the background.  You consider that a nice feature, which it is; however, there could be nefarious people nearby lurking about seeking your information.

If you have a VPN connection on your device, you log in with your own username and password to a server at another location.  It is similar to “drilling” a tunnel through the local internet Wi-Fi connection you are on.  That stops anyone from seeing what you are sending or receiving, keeping your information private.   This includes your login and all transactions on your bank account if you use it while there.  All banks use “Hyper Text Transfer Protocol Secure,” you know the URL that starts with “https.”  That “S” means that it is secure but again someone may be digitally looking at your keystrokes while in the open and recording them for their use.  If you use a VPN they should be stopped dead in their tracks from getting your info.

The VPN encrypts the information you send to be unencrypted only by the person/organization to whom it is meant to be delivered.

Check the short video below to see how a VPN works. 
Sometimes pictures are worth a thousand words.

Also, many people use VPN for a location setting.  If they were to want to watch a TV show in a foreign country but it was not allowed out of that country, you could use VPN.  It would camouflage their actual location and appear to be in that country.  But they could actually be on the other side of the earth.  What if someone is in a county that will not allow free speech but wants to blog about the injustices or issues there?  With VPN they could do so and not be discovered by their governments.

This is only a high-altitude flyover of what a VPN is and how it can be used.  If you are interested look for more information online.  Remember, a VPN that you pay nothing for may be exactly what it is worth.  Shop around and read reviews as a good one will cost a little.

April 19, 2011

Excel Formula Auditing, Part 2

Last week we covered the first three items in Excel’s “Formula Auditing” tools: Tracing Precedents, Dependents, Remove Arrows and Show Formulas in Excel’s “Formula Auditing” tools. Today we will wrap up the last three features.

I am sure you have never seen an “Error” popup box in Excel. That’s not true, unless you are an Excel Pro and have never made a mistake. I picked one that is easy to reconstruct for this column.

“Error” popup box in ExcelI created a formula that divides a number by zero. I know you all know why you can’t do that. Okay, you were taught, but you don’t remember why not either. In Excel if you do that you will get, “#DIV/0!” which (if you speak Excel you know) means you cannot divide any number by zero (0). If you’re not sure what that means you can click the “Error Checking” button. This button is found under the Formula Tab and then in the Formula Auditing command group.

Once clicked, you get several options; “Help on this error,” “Show Calculation Steps,” “Ignore Error,” “Edit in Formula Bar” and others you can check out. This should help you figure out the error made and give you some guidance as to how to best correct it. The “Help…” link is usually the best to aid me.

Click the yellow diamond with an exclamation markAlso, keep in mind you can get this same help directly from the cell containing the error warning. You will get a little green triangle in the upper left corner of the offending cell. When you click on that cell you will see a yellow diamond with an exclamation mark in it. When you click on the exclamation mark you will get the same list of options you saw in the previous area and you may click on the one you choose.

Next is the “Evaluate Formula” button, which I am not that fond of; however, it may really pay off for you. It will basically walk you through a complicated formula step by step. This gives you the ability to evaluate how each part of the formula works and even if it does work the way you designed it to.

Finally, one of the neatest Excel tricks for auditing formulas: the “Watch Window” command. If you haven’t tried it before give it a shot now.

Let’s say that you are working on Sheet 3 in your workbook and want to view changes occurring in cell A10 on Sheet 1. This is hard to do until you use the “Watch Window” feature.

Watch WindowNavigate to the Watch Window button and click it. Now go to the sheet and cell you want to view and click on it. Click the “Add Watch” button at the top of the window and you will always see the Book and Sheet name along with the Cell Name, (if you have named it) the cell address, value and formula, no matter where you go with Excel. You will see any change reflected in the watch window where you can immediately deal with it or be advised what is happening.

Let me know if you appreciate these looks at Excel and if you would like to learn more, or if you would like to explore other Office products.

April 12, 2011

Excel Formula Auditing

At the end of last year I wrote a column with regard to Microsoft’s spreadsheet program Excel.  Due to the email response, (which to me at least was unexpected) it has now turned into three columns.  I guess there are more of you Excel users out there than I thought.

I have continued to get email questions about Excel, so today I thought I would give you a couple of other tips about auditing cells.  These are in response to reader questions.  Remember to email questions to me…I thrive on them.  (Well, OK, not really thrive, but I do like to get them.)

Show FormulasTip #1:  Sometimes you need to look at all of the formulas on a spreadsheet.  You can click on each cell containing a formula and look at the top of the Formula Bar.   But that takes a while and what if you miss one?  In Excel versions 2007 and newer, the way to see them all at once is to navigate to the Formula Tab on the ribbon, look to the right side and find the "Formula Auditing" commands.  Once there, click on the "Show Formulas" button.  There all of your formulas are displayed at once.  Click it again to turn them off.  Now here is a really neat shortcut.   Just use the "CTRL + ~" key combo.  (Press and hold the Ctrl key and then tap the tilde key.)  Works like a charm! You can be located anywhere in a workbook and it works every time for showing and hiding formulas.

Formula Audit commandsWhile at the "Formula Auditing" command area, let’s look at several more features.

 

Tip #2:  Trace Precedents and Dependents:  This may be too deep for you non Excel folks, but read on, you may add a couple of new words to your cyber vocabulary.  If you have a simple formula adding 1, 2 and 3 for a total of 6 (I hope you are all with me up to now at least) and something appears wrong you can poke around in the formula and figure it out.  Many times it is helpful to be able to view what your formula utilizes to find an answer.

Trace PrecedentsIn the formula above you can click on the cell with the answer/formula in it and click "Trace Precedents."  Poof, you get a little blue arrow showing you the cells used in the formula (shown on right).

Trace DependentsTo determine a dependent, click on one of the digits making up the list you are adding, say the "2".  Click "Trace Dependents" and you will get an arrow showing which cells in that spreadsheet depend on the value.  By using these two tools you can usually figure out why a formula is blowing up on you.  To clear the arrows, click the "Remove Arrows" button.

We will finish up formula audits next week and then move on from Excel…unless I hear from you.

Also, if you are a visual learner like me, you may want to visit the DoubleClicks.info site to see screenshots of what we talked about here.  (Hey, don’t worry, you are already here…have a great day!)

Powered by WordPress

%d bloggers like this: