If Word starts behaving very oddly, you may have caught a macro virus. One very irritating virus will let you save your document only as a template! This one was once quite common, so right after learning about templates seems a good time to discuss viruses that can infect Word documents and templates.
A macro is a set of directions for Word to do something automatically. Word comes with a long list of useful macros, including all the things you see done with buttons. You can write your own macro to do a sequence of steps that you do often.
Macros that are part of Word 2010
A virus takes advantage of this automation to do nasty things that you don't want to do at all! A macro virus often stores itself in the Normal.dotx template. This guarantees that all new files will be infected. Ouch!
The first macro virus was found in 1995. Before that, documents and templates could not transmit a computer virus. Oh, for the good old days!
You may have been infected by a macro virus if any of the following occur:
Email software may block Office documents from opening from inside the email interface. In that case, you must save the document and open it from File Explorer or from inside the program.
Don't ever open a document sent by email unless you were expecting it AND trust the sender, even PDF format documents. Be aware that many viruses steal email addresses from an infected computer and send themselves to the friends and co-workers found there! If your friend's computer catches a virus, it is highly likely that you will get a message that appears to be from him/her that will spread the virus to your computer.
From this list, you can see how easy it is to get infected by the same virus many times by accessing files in places that you did not know it had infected. That's why the best idea is to avoid catch a virus at all!
If the virus you caught turned your document into a template, after you have disinfected the computer, you still must change the template back into a document. The procedure below is awkward but it works.
Click on the Office button or File tab and then on New.
Navigate to the document that is not
supposed to be a template.
It may be in Recent Templates or Featured. In Word 2007 and 2010 you can use
New from Existing.
A new document appears using the template, but you cannot just save the new document as a Word document. That option is grayed out! It's part of the evil plan of the infection!
Word can warn you every time you open
a document that contains a macro. But Word can't tell if this is a macro virus or a useful macro that is an ordinary part of
a document.
You can select how protective you want Office to be in the Microsoft Trust Center, which is part of Microsoft Office.
Office button or File tab > Word Options > Microsoft Trust Center > Trust Center Settings... > Macro Settings > Disable all macros with notification.
You can learn the latest about macro viruses from the web site of your anti-virus software or Search Microsoft's Knowledge Base with the phrase macro virus.