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DADDY BOB'S COMPUTER Q & A
July 11, 2010
Q.
I’m trying to open a document and it is
asking me something about enabling macros.
Just what is a macro, and should I enable
them?
A.
The word macro means big or large
and as related to computing probable comes
from shorting the tern, macroinstruction.
Macros are used in programming, especially
in assembler or machine language
programming. This type of programming is at
the lowest level, and requires many lines of
code to perform a simple action. To
alleviate the need to re-enter the same
lines of code over and over again, a macro
is created that automatically enters the
specific lines when the source is compiled.
Now, the
programming macro is not what is being
referred to in this case, but the word macro
has carried over to actions that are used in
many programs. A macro in this case, is a
symbol, name, or key press that represents a
list of commands, actions, or keystrokes.
Many programs allow you to create macros so
that you can enter a single character or
word to perform a whole series of actions.
Programs
like Microsoft Office allow you to record
your own macro. You could use a macro to
enter words or phrases that you use
frequently. For example, you could record a
macro that contains all the keystrokes
necessary to enter your letterhead -- your
name, address, a code that inserts the
current date and even a graphic. Then,
whenever you write a letter, you just press
the macro key to automatically enter the
letter header.
So, why
is something that appears to be so helpful
the cause for a security warning? A
person with malicious intent can embed a
destructive macro, in a document or file,
which can spread a virus on your computer.
This macro may remain dormant until a
certain key sequence is pressed or execute
immediately when the document was opened.
Macros
have been used in one form or another for
years but it wasn't until Microsoft allowed
macros created with Visual Basic to be used
that it opened a can of worms. One
especially widespread macro virus called
Melissa spread in 1999 and caused many
problems.
Melissa
arrived as an attachment to an e-mail note
with the subject line "Important Message
from ......." and body text that reads "Here
is that document you asked for...don't show
anyone else ;-)". The attachment was often
named LIST.DOC. If the recipient clicked on
or otherwise opened the attachment, the
macro was activated and the virus file was
entered into to computer's memory.
The virus
then created an email using the Visual Basic
code, read the first 50 names in your
Address Book, and sent each of them the same
e-mail with virus attachment that caused
this particular infection. Fortunately, this
particular virus only worked with Outlook
and not other email programs or its effect
would have been much worse.
In some
less frequent of cases when a certain
criteria was met, this phrase was inserted
at the cursor location. "Twenty-two
points, plus triple-word score, plus fifty
points for using all my letters. Game's
over. I'm outta here." The quote refers
to the game of Scrabble and is taken from a
Bart Simpson cartoon.
To head
off these kinds of macro viruses, latter
versions of Office and other programs were
installed with the macro capabilities turned
off. So, when you open a document that may
contain a macro, the program asks you if you
trust the sender and want to allow the
macros to function. This is also why most
current ISPs do not allow the sending of
documents as attachments to emails.
Fortunately, these preventative measures had
all but eliminated the macro virus problems.
The
ability to record macros has also been made
more difficult to do starting with Office
2007 and carried through Office 2010. This
feature is turned off by default, and to
record a macro the Developer tab in the
ribbon has to be turned on. In Office 2003,
all that is required to record a macro is to
select Tools, Macro, then Record new macro.
In Office
2007, click the Orb then the Word Option
button. Check the box in front of "Show
Developer tab in the ribbon". Then click on
the Developer tab and Record Macro. In
Office 2010, click File. Options then
Customize Ribbons. On the right side, select
Main tabs, then check the box in front of
Developer. Click the Developer tab, and then
New Macro.
The
default action of how to handle a macro can
be changed. Most versions give you four
choices. 1. Disable all macros, 2. Disable
all macros with warning (the default), 3.
Disable all macros except those with digital
signatures, and 4, enable all macros. Office
2003 and later versions add one more choice;
the ability to trust access to VBA projects.
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