iMac 7.1 on Mavericks issues
I have two concerns with our iMac. Has it been hacked or is some sort of instability developing?
We have a 2 GHz iMac 7.1 running Mavericks 10.9.5. It has 6GB Ram. We use Firefox. OSX was upgraded to Mavericks when it was released. The iMac worked fine. Then OSX was upgraded to Yosemite. This was unstable and clunky to use so Mavericks was reinstalled a year ago. This has worked fine but recently two issues have appeared.
Software Update is run every week and all Security, iTunes, Safari and other updates are installed. There was no problem until I recently tried to run Software Update. Instead of the usual response, a window opened asking for a FaceTime Password. Trying again resulted in another window asking for an iMessage Password. Each time the window asked me to enter my password for a gmail address that is rarely used. I clicked on “Cancel” each time. We have never used either of these apps. A quick online search showed that others have experienced the same issue. Following the online advice I then (for the first time) opened these apps and ensured that they were turned off. The problem has not happened since. What caused it?
Next, we save some documents and screen shots on the Desktop. On booting these normally show as small versions of the Pages, docx, png or pdf documents. Recently sometimes on booting these documents show as small generic icons for Pages, jpg or pdf. Surely they should show the same every time, as they did until a few weeks ago. Why is there this instability?
I have run Sophos Anti-Virus and Disc Utility. Sophos does not find any problem and Disc Utility shows the same few minor issues that it has always shown.
When we had a PowerMac 6100/66 it was necessary to occasionally reinstall the OS and to reset the PRAM. Is there some similar process needed for OSX? The odd part is that these problems have appeared in just the past four or five weeks.
I will appreciate some advice.