Firstly, I do not have iCloud, iPhoto, Aeroglass or Bitdefender, which have been cited by others as culprits for this issue. The AV is McAfee.
I have updated three other PCs to Windows 10 without incident, including an older Dell Inspiron, but my parents' Dell Inspiron N5040 laptop has been a real headache. The migration was from Windows 7 Home Premium 64 bit to Windows 10 Home via online upgrade. Prior to the upgrade the laptop had been behaving quite normally.
The outstanding issue is that every few minutes and without warning the Desktop and Task Bar refresh automatically. If you are in Windows Explorer or the Control Panel when this happens, you are ejected. If you are in an application, the app loses focus and you lose anything you have just typed. The laptop is usable, but the problem is very irritating and likely to deter my mother from using it.
Task Manager showed that CPU usage was momentarily spiking at 100% when these refreshes occurred, but didn’t help at the process level, so I downloaded and ran Process Explorer. This shows that, when these refreshes happen, there are momentary peaks of activity in ShellUI.exe and ShellExperienceHost.exe, the former apparently fractionally ahead of the latter. I have turned off Cortana and all the other user-adjustable search settings, but it makes no difference. There appears to be no way to disable these processes. I do not have the Desktop set to display a slide show, merely a still image. I have also used a solid colour; no difference.
The Win 10 compatibility report suggested all would be well, but the upgrade was difficult. For my first attempt I used the Win 10 upgrade icon in the Task Bar. I let it run for quite some time but it appeared to have hung. I then used Media Creation Tool, this got to the end of downloading but announced that it could not perform the upgrade on this particular computer, citing error code 0x80070005 – 09x90002. Following advice on an MS page, I downloaded the SubInACL Tool and created a Reset.cmd file, which I ran as administrator to fix registry permission errors which can cause this error. I then ran used Media Creation Tool again and the upgrade completed. However, the screen then started flashing on and off so rapidly (every second or so) that the laptop was impossible to use. I’m not the only one who has had this, and I discovered the fix was to disable two MS services, ‘Problem Reports and Solution Control Panel Support’ and ‘Windows Error Report Service’.
Now I am left with the maddening screen refresh issue, which was not present before the upgrade. I know others have had this problem, but I haven’t as yet come across a solution. I know Dell are not supporting this model under Windows 10, but can anyone help please?