Copy Protection Technique Using GetAttr Function

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Author:
N.Narayanan

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COPY PROTECTION TECHNIQUES USING VISUAL BASIC CODE
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Here I have analyzed about what happens when a file is copied from one place to another place.

If you ever look at the functionality of Utility Softwares like MS-BACKUP and others, there is one option called incremental backup. What does it mean? Incremental Option, backups only the files which are changed since last backup. How does the Utility Software identify whether a file is changed or not? Here comes the Archive Bit. Normally backup software removes this bit, after the backup. This bit is automatically enabled when it is modified.

And I found that same thing happens when you copy a file from one place to another place. I.e. first you remove the archive bit of a file (in DOS issue the command ATTRIB myfile.txt -A) and then copy the file to another place. Now the copied file's archive bit is enabled.

So, when you install your software, you remove the archive bit of any component. Inside the software you have a check whether the component's archive bit is enabled, if so come out.

This works fine, since in the Original Place where we installed the software does not have the archive bit set. But if any one copies, the target files archive bit is enabled automatically (This is default functionality of copy function).

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Instructions: Copy the declarations and code below and paste directly into your VB project.

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