Sometimes an application stops behaving properly and doesn’t respond to menu commands or keyboard commands. When this happens you’ll often want to use the Force Quit command to force the application to quit. There are several ways to issue the Force Quit command.

1. The easiest way is to click on the Apple menu and select Force Quit. A window will pop up listing all of the applications which are currently open. Click on the one that you want to force quit and then click the Force Quit button in the lower right corner. You’ll be asked if you’re sure that you want to do this. Click the button to indicate that you’re sure.

If the Apple menu is not responsive then you may not be able to use this method. In this case, try the next method.

2. Hold down the Option key while simultaneously clicking on the Dock icon for the application which you want to force quit. A menu should pop up after a couple of seconds. Select Force Quit from this menu.

If the Dock is not responsive then you may not be able to use this method. In this case, try the next method.

3. Simultaneously press the following 3 keys, Command, Option and Escape. The Escape key is labeled “esc” and is above the “1″ key. A window will pop up listing all of the applications which are currently open. Click on the one that you want to force quit and then click the Force Quit button in the lower right corner. You’ll be asked if you’re sure that you want to do this. Click the button to indicate that you’re sure.

If none of these methods work then you aren’t able to force quit applications. Typically, the only option at this point is to force the computer to turn itself off. This is accomplished by pressing and holding the Power button for 5 seconds. The power button is the round button you use to typically turn the computer on. Hold this button for 5 seconds. The entire computer will turn off and the screen will go dark. Then press and release this power button to turn on the Mac.

Firefox and Safari for Mac are the two most popular web browsers for Mac users. At times, both of them can act up and not perform properly. When this happens, here are a couple of basic troubleshooting steps which you can take.

In Safari, go to the menu named Safari and select “Empty Cache”. This will remove the locally saved (cached) copy of recently visited web sites. This might be all you need to do to fix your problem. If not, you can continue by going to the Safari menu and selecting ”Reset Safari”. This is a very handy feature since it lets you easily remove some of the information which it saves which can get damaged and cause Safari to misbehave. By default, all of the options are checked in the Reset Safari window. Typically, I recommend that you only select and reset the following since they seem to cause the most problems:

• Remove all webpage preview images
• Remove all website icons

If your Safari problem is not resolved then you can go ahead and select other items to reset, but be aware that removed saved names, passwords and AutoFill data can mean that you’ll be prompted to re-enter this information down the road. Consequently, I try to reset these items last.

Firefox doesn’t have a handy reset feature the same way as Safari. However, you can empty its cache by doing the following. Open Firefox and go to the Firefox menu, select Preferences, click on Advanced and click on Network. Click the “Clear Now” button in the Offline Storage section. To do more advanced troubleshooting in Firefox, I recommend checking out this helpful troubleshooting article written by the makers of Firefox.

Did you know that Apple’s Preview lets you easily annotate PDFs, merge PDFs as well as delete and re-order pages within a PDF? Preview is a free application which comes bundled with Mac OS X. Apple has been quietly updating over the years and it has become quite capable and user-friendly. Just a few years ago one would have needed to buy the relatively expensive Adobe Acrobat Standard or Professional PDF Editor to do many of these tasks.

I should note that there are slight differences in how certain tasks are done if you’re using OS X 10.5′s version of Preview. All of these demonstrations are done using OS X 10.6′s version of Preview.

It’s also important to know that the following techniques may not work on all PDFs. It’s possible for a person who creates a PDF to lock the file in such a way as to prevent others from manipulating it. Typically, locking a PDF like this requires use of an application like Adobe’s Acrobat.

I’ve created short video tutorials on how to do the following tasks. Read the brief text description and then click the link to watch the video.

If you need more extensive editing capabilities then what is offered by Preview then you should check out the relatively affordable PDFPen.

1. Reorder pages in a PDF – Open a PDF file, click the Sidebar button to view the thumbnail icons for each page. Click on one of the thumbnails and drag the page up or down. Look for the horizontal blue line that appears indicating the new location of the page. To remove a page you can simply click on the thumbnail icon for a page to select it and the press the Delete key on your keyboard.

2. Extract pages from a PDF – Open a PDF file, click the Sidebar button to view the thumbnail icons for each page. Click on the first page you want to extract. If you want to extract additional pages then hold down the Command key and click on additional thumbnail icons. Release the Command key and then drag the thumbnail icons to the Desktop. A new PDF file will be created on the Desktop. Rename the file as desired. Open this new file by double-clicking to verify that it contains the pages that you want. You can re-order the pages by following the tip listed above.

3. Move pages between PDFs (Merge PDFs) – Open a PDF file, click the Sidebar button to view the thumbnail icons for each page. Open a second PDF and click its Sidebar button too. Position the two PDFs so you can view both file’s Sidebars at the same time. Select one or more pages from one file’s Sidebar and drag them into the other file’s Sidebar. Look for the horizontal blue line that appears in the receiving file’s Sidebar. This blue line indicates where the new page appear. You can re-order the pages by following the tip listed above. Go to the File menu and select Save to save the changes.

4. Annotate text in a PDF -  Open a PDF file, click the Annotate button to review a row of tools at the bottom of the window. Use these tools to highlight text in a variety of colors, draw a line through the text, enclose text inside a rectangle or oval, add a note in the margin of the PDF.

Are you having difficulty getting Verizon Wireless UMW190 Aircard working on your Mac running OS X 10.6? If so, make sure you’re using the proper version of VZAccess Manager. I know that the UMW190 works with version 7.0.5.

Verizon Wireless’ web page for Support Devices & Platforms lists the incorrect version of VZAccess Manager. It indicates that if your Mac is running OS X 10.6 then you should use VZAccess Manager version 7.2.1 (2595a). This is incorrect. I spent a long time banging my head against the wall. You can install version 7.2.1 and your UMW190 will be able to establish a connection to Verizon Wireless. It even gets an IP number assigned, but it can’t ping its WAN IP number, it can’t ping typically available public IP numbers and it doesn’t respond to pings. I spoke to Verizon Wireless tech support on a handful of occasions and we repeatedly reviewed which version of VZAccess Manager I had installed. I indicated version 7.2.1 and none of them indicated that this was wrong. So, either they refer to the same web page that I found or their internal documentation lists the wrong version also.

The clue that lead me to try the “wrong” version was the ReadMe file for the 7.2.1 Installer. I read through the list of supported Aircard devices and the UWM190 wasn’t listed. I then revisited Verizon Wireless’ Supported Devices & Platforms page and saw that the UMW175 and UMW 150 cards use VZAccess Manager 7.0.5.  I guessed that the UMW190 was probably a pretty similar device. I downloaded version 7.0.5 and read its ReadMe file. Sure enough the UMW190 was listed! I installed this version, restarted my Mac, established a connection. Voila. That was it. Everything worked. I was able to view web pages and send and receive email.

Did you know that Mac OS X has a built-in zoom feature? This feature lets you zoom in on your screen so everything on the screen is larger. Of course, when you zoom in you can only see part of the screen on your monitor. You need to scroll around to see the other parts of the screen.

I use the zoom feature frequently when I’m giving presentations especially when I provide Mac training. I project my Mac laptop’s image onto a wall or screen using a projector. Then, I want to show audience members something on the screen so I zoom the screen so I can ensure that everybody in the audience can see what I’m trying to highlight on one part of the screen.

Zoom is off be default. Follow these instructions to turn it on.

• Go to the Apple menu and select System Preferences.
• Click on the Universal Access icon
• Click on the Seeing button.
• In the Zoom section set the button to On.
• Optionally, click the Options button and make sure in the section titled “When zoomed in, the screen image moves:” that it is set to “Only when the pointer reaches an edge”. Click Done. The other options lead to too much screen movement which I find distracting or even annoying.

Once the zoom feature is enabled then you can invoke it at any time to zoom in on your Mac’s screen by simultaneously pressing these 3 keys: Command, Option and the Plus Sign (which is typically the same as the Equal Sign key). Each time you press these three keys your Mac will zoom in a little bit more.

To zoom out simultaneously press these 3 keys: Command, Option and the Minus Sign key which is typically to the left of the Plus Sign key.

Do you want to give your computer to another person so they can use it, but before you give it away you want to remove all of your data? If so, here’s an easy way to accomplish this. We’ll create a user account for the person who’ll be using the Mac, then we’ll delete your user account.

These instructions were written for OS X 10.5 and 10.6, but should work on previous versions as well though some of the names and wordings have changed subtly.

• Turn on the Mac and let it start up.
• Go to the Apple menu, select System Preferences and click on Accounts
• If the padlock in the lower left corner is locked then click on it to unlock it. Enter your user account’s password when prompted to do so.
• Click the plus sign button to add a new user account. Set “New Account” to “Administrator”. Enter the real world name of the new user of the Mac in the “Full Name” field. Enter a name in the “Account name” field; this name can not contain spaces, capital letters or punctuation marks. Enter a password in both the “Password” and “Verify” fields. Enter a password hint if you’d like.
• Click the “Create Account” button.
• Go to the Apple menu and select Log Out which appears at the bottom of the menu.
• You’ll be presented with a login window. Type in the account name and password for the account which you just created. You’ll be logged into this new user’s account and now that you’re no longer using your account it can be deleted.
• Go to the Apple menu, select System Preferences and click on Accounts
• If the padlock in the lower left corner is locked then click on it to unlock it. Enter your user account’s password when prompted to do so.
• Click on your user account which’ll be listed on the left-hand side of the window.
• Click the minus sign button to delete your user account.
• Select “Delete the home folder” to have all of the data in your user account deleted.
• Click the OK button. The actual deletion process could take 10-15 minutes, especially if there is a lot of data in your account.
• When the deletion process is complete you can close the System Preferences window.

Here are instructions on how to use Disk Utility to securely erase a hard drive connected internally or externally to your Mac. These instructions were written for Mac OS X 10.4 to 10.6. The process is very similar on older versions of Mac OS X but the screens will look a bit different.

Requirements – You’ll need either the Mac OS X install disk that came with your Mac or another OS X install disk that’ll boot your Mac, such as a retail copy of the Mac OS X 10.5 or 10.6 install disk.

I recommend securely erasing a hard drive before you recycle it or give it away. The instructions below include the option to re-install Mac OS X onto the hard drive at the end of the process.

If you’re securely erasing an external hard drive you do not need to use a Mac OS X install disk. Instead, you can simply open Disk Utility which you’ll find in the Utilities folder inside the Applications folder. In Disk Utility, select the external hard drive and then follow the last few steps below to erase it using one of the Security Options described below.

Background – Technically, it’s not possible to erase or remove data from hard drives. Thus “securely erasing” is a misnomer. Instead, what we’ll be doing is over-writing the data on your hard drive with gibberish, a random string of bits of data. When you securely erase your hard drive you’ll have a choice of how much over-writing you want to do. This process can take many hours if you select the 7-pass overwrite procedure. I recommend starting this process and then letting it run over-night.

• Insert the Mac OS X install disc that came with your Mac.
• Note: The disc will begin the process of installing Mac OS X on your Mac. Whether or not you actually choose to install Mac OS X is your choice, but if you do, you’ll do it AFTER you’ve securely erased your Mac’s hard drive.
• Select your preferred language from the list presented.
• When you see the welcome screen for the Mac OS X Installer go to the menu named Utilities and select Disk Utility
• In the left pane of the Disk Utility window, click on the hard drive you want to erase.
• In the right pane of the Disk Utility window, click the Erase tab.
• Click the Security Options button
• I recommend that you select the 7-Pass Erase options, but you could choose the 35-Pass Erase option. Here’s my description of these options.

Don’t Erase Data— This option does not provide any security. This option only over-writes the directories on the hard drive. Your files could still be recovered.
Zero Out Data— Provides a pretty good level of security. All of your files are over-written with a string of zeroes. There are forensics utilities that in theory could retrieve some data.
7-Pass Erase— Provides a lot of security. This is considered sufficient by government standards to erase data from a disk. It writes a random string of ones and zeroes over your data files seven times. It may take several hours or more to complete this process.
35-Pass Erase— Provides the maximum amount of security offered.This option takes an extremely long time, possibly more than one day.

• Click the radio button in front of 7-Pass Erase
• Click OK.
• Click the Erase button next to the Security Options button.
• Confirm you want to erase and the process will be begin.
• If you want to install Mac OS X then go to the Disk Utility menu and select Quit
• You’ll be taken back to the Mac OS X Installer welcome window. Click Continue.
• Agree to the software license.
• In the “Select a Destination” window click on the icon for the hard drive which you just erased and then click Continue.
• Click the Install button to start the installation process. Depending upon the speed of your Mac and the version of Mac OS X which you are installing this process could commonly take anywhere from 20-60 minutes.