Microsoft Mouse and Keyboard Center doesn't recognize Sculpt Comfort Keyboard (Windows 8.1 x64)

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In other words, it fails to recognize Sculpt Comfort Keyboard when it's alone, and recognizes it just in pair with mouse.

The problem now is that I don't know what to do with single keyboard now ]:->

Microsoft sells the Sculpt Comfort Desktop, but they are not listed here either: http://www.microsoft.com/hardware/en-us/help/windows-8/troubleshooting/mouse/supported-devices

Only the Sculpt Comfort MOUSE is there, the Keyboard and Desktop are not. Do you agree?

That can be called an awkward mistake made by Microsoft for sure.

I've got the same issue here, the Microsoft 2.3 program does not recognize the Sculpt Comfort Keyboard. 

Instead, it works properly on my desktop.

And as you guys did, I also noticed that the Sculpt Comfort Keyboard isn't listed at this page: http://www.microsoft.com/hardware/en-us/help/windows-8/troubleshooting/mouse/supported-devices

I think that is not the explanation but might be the reason of this problem. I can not understand why Microsoft did not include this keyboard (which I liked a lot) on the Microsoft Mouse and Keyboard Center list, even in it's most recent version (2.3.145)

There is no version 2.3.145 available for download from the official Microsoft hardware support website that I could find anywhere there.  The latest version available is 2.2.173.0.  You may well have installed hidden malware--and as yet unidentifiable because too new for current detection signatures--on your PC from the file download site where you obtained the unofficial driver.  Hopefully not but that is the chance you take when installing unofficial drivers and software from third-party sites.

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In other words, it fails to recognize Sculpt Comfort Keyboard when it's alone, and recognizes it just in pair with mouse.

The problem now is that I don't know what to do with single keyboard now ]:->

Microsoft sells the Sculpt Comfort Desktop, but they are not listed here either: http://www.microsoft.com/hardware/en-us/help/windows-8/troubleshooting/mouse/supported-devices

Only the Sculpt Comfort MOUSE is there, the Keyboard and Desktop are not. Do you agree?

That can be called an ackward mistake made by Microsoft for sure.

Microsoft has updated hardware components.  They are not under obligation to support older hardware constructs when newer is available or when they discontinue an older version or other hardware series.  They aim for backward compatibility but this is not always possible.

For those with older hardware (yes, even the retail and online stores still sometimes sell outdates hardware) they are recommending uninstalling mouse and keyboard center and using the IntelliPoint Software instead.

There is no version 2.3.145 available for download from the official Microsoft hardware support website that I could find anywhere there.  The latest version available is 2.2.173.0.  You may well have installed hidden malware--and as yet unidentifiable because too new for current detection signatures--on your PC from the file download site where you obtained the unofficial driver.  Hopefully not but that is the chance you take when installing unofficial drivers and software from third-party sites.

I am Brazilian. And I downloaded from the Microsoft pt-br site the 2.3 version, you can check by your own here http://www.microsoft.com/hardware/pt-br/p/sculpt-comfort-keyboard/V4S-00005#support

You might not speak Portuguese, but you can understand this at the 'Suporte' section and then 'Softwares e Drivers'. 

I took a look at the English site too and I noticed that YOUR latest version is the 2.2

What is happening here?

There is no version 2.3.145 available for download from the official Microsoft hardware support website that I could find anywhere there.  The latest version available is 2.2.173.0.  You may well have installed hidden malware--and as yet unidentifiable because too new for current detection signatures--on your PC from the file download site where you obtained the unofficial driver.  Hopefully not but that is the chance you take when installing unofficial drivers and software from third-party sites.

I am Brazilian. And I downloaded from the Microsoft pt-br site the 2.3 version, you can check by your own here http://www.microsoft.com/hardware/pt-br/p/sculpt-comfort-keyboard/V4S-00005#support

You might not speak Portuguese, but you can understand this at the 'Suporte' section and then 'Softwares e Drivers'. 

I took a look at the English site too and I noticed that YOUR latest version is the 2.2

What is happening here?

What is happening? That is a very good question.  I do not know.  That is interesting, though, that the other-language support site got newer drivers and software first.  Hopefully the English sites will see the same soon.