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EXCEL DATA ANALYSIS

SET MACRO SECURITY

hether you create your own macros for data • Medium: This level of security enables you to specify
analysis, or open workbooks created by other whether you want to run macros from trusted and
W users containing macros, you need to specify unsigned sources when you load Excel. Select this level if
your macro security settings. Due to the increasing problem you want to eliminate the hassle of signing the macros
with computer viruses, specifically macro viruses, by default that you create.
Excel disables all macros in worksheets that you open • Low: With this level, Excel automatically loads all
except ones with digital signatures from trusted sources.
workbooks and macros without checking to see if they
Digital signatures, which macro creators use to verify their are from trusted sources. With this setting, the only
macros' safety, remain attached to a macro or other file as protection from macro viruses is a good virus scanner.
long as no one modifies the macro or file. Macro To eliminate the hassle and expense of acquiring a digital
modifications require you, as the creator, to reattach the certificate, you can personally sign your macros by running
signature. A macro with a valid digital signature confirms selfcert.exe, an Office XP program. Creating and
the macro's origins and that no one altered it.
attaching your personal signature indicates that you certify
There are three different security settings you can select for the security of a macro, identifies the macros that you
macros: create, and distinguishes your macros from other macros.
• High: The default security level for Excel. This level
disables all unsigned macros, even ones that you create.
You have the option of selecting macros from other
trusted sources when you run Excel.
SET MACRO SECURITY

SET SECURITY ■ The Security dialog box ‹ Click the desired security
opens. level.
⁄ Click Tools ➪ Macro ➪
Security. ¤ Click the Security Level › Click OK.
tab.
■ Excel assigns a security
level.

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