HarryTri

Impossible - may be it is a hidden file? Also you 'd rather scan your system for viruses with a good AV program - I personally recommend AVG or ClamWin.

Have you tried changing the folder's permissions?

It seems that your Administrator account was corrupted and Windows created a new Administrator account. You can try deleting this account, all the files of Administrator and Administrator.xxx user folders (backup what you want to preserve first), all the related registry entries, reboot and then try creating the account again. If you have System Restore enabled and a system restore point prior to the incident just use it and it will probably restore everything (since it contains the SAM and SECURITY files of the registry which have to do with the user accounts).

Windows 8.1 doesn't inform you when there are files with the same name in the destination folder? Windows 8 at least does.

Each SP is supposed to include all the updates that were released before it.

Still there is the wbadmin command, right? It may not have the same options with the vssadmin but it utilizes the VSS functionality. Noel, aren't you making your backups with it?

Well, they are supposed to be contained in the Service Pack and will be uninstalled (at least their registry entries) at its installation.

Search your computer for an F.exe file, it may be a virus or anything like that... Sorry, you said it is in the Applications tab? Right click on it and click on "Go to the process". In the best case this will lead you to Windows Explorer and it is just an F: drive's root folder opened.

Perhaps Windows 8 are more verbal than Windows 7 and report everything even if it is trivial.

In order to check the temperatures you can install HWiNFO (http://www.hwinfo.com/) which gives detailed information about them (in the sensors tab) and the system in general.

I found a freeware program that is called System Explorer and among other things has an interface similar to Autoruns for the startup items: http://systemexplorer.net/

Probably it's just that Windows is "perceiving" itself as newly installed after the change of the product key, hence the "initial" full backup.

That's life... Yet you could just restore your system from your system backups and pay no money. Anyway I don't believe that Microsoft is waiting to make money from people who haven't used it's activation keys for two years, it just happened. At least we know now that these keys expire sooner or later if they are not used (it would be good to know the exact time needed for this to happen).

Windows Defender is to be disabled if you have a "normal" antivirus program installed.

Yes, that's it but the restoral capability must exist somehow in Windows 8.1 too (if not then the system backup is useless, at least for the not-too-geek user). Maybe in the Recovery option in your first image?

How is it possible? I mean a clean install starts with a disk format, doesn't it? Except if the preserved data are copied to another drive first.

That's exactly what I meant but it seems that they moved this functionality to the File History panel per what you say.

It is in Windows 8 and must be in Windows 8.1, have a look at the Control Panel>System and Security>File History and it is in the "See also" section down in the left.

Yes, that's a problem...

You can try using IE8, it isn't so horrible as they say. As for security, I think the post-SP3 updates (I suppose you have SP3), a good antivirus and - ideally - a good router with firewall will suffice.

There is also the "Windows 7(?) file restore" or something like that (I translate from Greek) in the control panel which in fact has to do with disk backups - as I found by chance - and is probably the GUI analog to wbadmin.

Well, everything seems to be a driver issue. As I found in the web a lot of people have this problem not only with Conexant but with Realtek high definition audio devices too. In all the cases - including mine and that's what I ended up to - installing the Windows generic drives for high definition audio solves the problem. A conflict of the OEM drives with a Windows Update or something else (thought I uninstalled most of my programs trying to find a cause of the problem to no avail), who knows? Anyway at least there is a working alternative/solution at least.

The sound disappeared again... It was the only time that the sound came back without a reboot and it seems that it was a weird coincidence. I run a system diagnostic and it says that everything is all right... I don't know what to think of anymore.

I found it! \Microsoft\Windows\Multimedia\SystemSoundsService in Task Scheduler. I stopped it and the sound came back immediately!. I deactivated it of course...

Thanks for the reply. I tried to troubleshoot the problem by watching the sound function and checking what is writen in the event logs at the time that it disappears and l ended up disabling the Lenovo Security Center service, this seems to make the difference as far as I don't open Lenovo Security Center (version 2.4.003) itself. I hope that this is really the cause, you can much more easier copy with a problem if you know what causes it. No, it wasn't... either. Noel, if you remember something more about what you red please tell me.