Read error messages and checkboxes…

When you see an error message pop up on the screen, read it! You may not understand everything, but if you look through the message, you can get the gist of it. Hackers can sometimes generate errors to collect everything you type and everything that comes up on your screen. If you don't understand the error, at least capture the screen. To do that, hold down the Alt key and press the key labeled Print Screen or PrtScn. That will put the screen shot into short-term storage called the clipboard. Then open an e-mail message, right click on the message body and select "paste". Now you can print it or send it to tech support for further analysis.   Source: SANS Institute