Last week two people asked me the same question "why can't I open attachments my friends are sending me?".

In both cases the file names ended with .docx. The solution is very simple, download and install the "Microsoft Office Compatibilty Pack"

When I told one friend this they said they had already done that but it still wouldn't work. After a bit of investigation I found that they had indeed downloaded it but hadn't installed it.

One of my pet peeves is people typing their message into a Word document and then emailing that as an attachment. Why don't they just type the message into the email message? But they do and so we want to be able to read them.

First make sure that you do actually want to read the attached message. Bogus attachments from people who have "spoofed" your friends email address are quite a common way of distributing nasty files that will compromise your computer's security. If you know the email is from someone you know and in the body of the email message it says that there is information in the attached document they want you to read then you probably want to read it.

Now make sure you have a virus scanner installed and that it is up to date.

A file with the DOCX file extension is a Word Microsoft Office Open XML Format Document file. Microsoft introduced this in Office 2007. Version of Word before 2007 don't know about the DOCX extension and so wont open them without the fix contained in the "Microsoft Office Compatibilty Pack".

When you click "Download" on a file you will get various options, depending upon which version of Windows and which browser you are using. Download is saving the file to our computer, installing is a separate process. After downloading you double click on the downloaded file to run the installation process.

Usually one option will be to download the file to your computer and another will be to "Run" the file directly from where it is. I always download to my computer first then run it, that prevents the installation stopping if I lose my internet connection.

The problem many people have with downloading a file is that they don't know where the file gets downloaded to. By default older versions of Windows will put the files into the My Documents/Downloads folder but this can be changed. Use Google to find how to change the download location on your browser.

Pay careful attention to the windows that appears after you click download it should tell you where the file is going to be put. Sometimes you'll see a check box that says "Close this Window when download is complete" you don't want that to happen so click the wee box so it doesn't close and then when the download is complete it will leave you with options to open the folder the file is in or run it.

Once you've installed a patch like this there is no need to keep the original installation file, it can be safely deleted.