Generally, changing the file extension of a file is not a good idea. Changing file extensions is usually unnecessary because files typically already have the appropriate extension. When you double-click a file that has the right extension, it will open with the correct program. For example, a file with a .txt file will open in a text editor, and a file with a .jpg extension will open in an image viewer.
If you change a file's extension, it may cause the file not to open.
Sometimes, changing a file extension may be a good idea.
While file extensions should typically be left alone, there may be times when changing a file's extension is the only way to get it to open. For example, you may receive an e-mail attachment called "report.pdf" that is actually formatted as a Word document.
When you double-click the file, Acrobat Reader will most likely try to open the file, since Acrobat Reader is what most computers use to view PDFs. Since Acrobat Reader is expecting a PDF, when it encounters a Word document, it may not be able to open the file. If you change the filename to "report.doc," the file should open in Microsoft Word. Since the file type is a Word document, the file should open without a problem.
Changing a file's extension can "force" the file to open in a different program. This can be useful when a file will not open using the default program. However, a better way to change what program opens a certain file is to modify the file's properties.
Sometimes, changing a file extension may be a good idea.
While file extensions should typically be left alone, there may be times when changing a file's extension is the only way to get it to open. For example, you may receive an e-mail attachment called "report.pdf" that is actually formatted as a Word document.
When you double-click the file, Acrobat Reader will most likely try to open the file, since Acrobat Reader is what most computers use to view PDFs. Since Acrobat Reader is expecting a PDF, when it encounters a Word document, it may not be able to open the file. If you change the filename to "report.doc," the file should open in Microsoft Word. Since the file type is a Word document, the file should open without a problem.
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