I agree that it is probably due to malware. I run Spybot - Search & Destroy but the problem still occurs. I have a related problem with DELETE in that on occasions when I click on it 'Read ade.yming.com' comes up down at the bottom LH and 'Loading .....' appears up top. This can go on for minutes. I can get rid of it by re-booting.
I have another computer with Windows 7. I believe my best move is to always use it for Internet and this one for Word and Excel. I have been slow in transferring to the new computer because I have been using this one for over a decade so was familiar with its mode of operation. However, problems are now making it difficult to use. Often now, an error message crops up and response stops as I am trying to interrogate a site. It reads 'Warning: Unresponsive script. Script on this page may be busy.' I have to click on 'Stop script' or 'continue' to get rid of the message.