how to slipstream 8.1?

Thank you for your reply.  8.1 ISO is the standalone DVD that is available for sale in an OS box, right?

Lets say I can get 8.1 ISO, would I still be able to use my 8 Pro key to install 8.1 ISO?

No you cannot you must use a generic install key to install depending on your version (likely 8.1 Professional). This gives a trial which allows you to install; if you go to system properties then you can input your actual Windows 8 (or 8.1) product key and activate.

In previous versions, it was possible to install Windows without key, run it as trial for up to 120 days, and enter a product key later. This option on first sight seems to have been removed in Windows 8.

However, it's still possible to pre-install Windows 8 or Windows 8.1 with a generic key. These keys can only install Windows. It's not possible to activate it unless you enter an original key purchased from Microsoft. Here they come...

XKY4K-2NRWR-8F6P2-448RF-CRYQH (Windows 8 Professional)
RR3BN-3YY9P-9D7FC-7J4YF-QGJXW (Windows 8 Professional with Media Center)
FB4WR-32NVD-4RW79-XQFWH-CYQG3 (Windows 8 [Home])
XHQ8N-C3MCJ-RQXB6-WCHYG-C9WKB (Windows 8.1 Professional)
GBFNG-2X3TC-8R27F-RMKYB-JK7QT (Windows 8.1 Professional with Media Center)
334NH-RXG76-64THK-C7CKG-D3VPT (Windows 8.1 [Home])

If you can get hold of the installation disk, you can use these keys to install now, and purchase an activation key after 4 months.

From: http://heidoc.net/joomla/technology-science/microsoft/70-windows-8-direct-download-links

so from what you are saying, it is not possible to use my 8 Pro key to install 8.1 Pro? because you said I have to purchase another activation key?

the only way for me to get 8.1 Pro is to install 8 with my key then upgrade 8.1 ?

so from what you are saying, it is not possible to use my 8 Pro key to install 8.1 Pro? because you said I have to purchase another activation key?

the only way for me to get 8.1 Pro is to install 8 with my key then upgrade 8.1 ?

If your doing a clean install, your win 8 license key should work with the win 8.1 ISO found here:

http://windows.microsoft.com/en-us/windows-8/upgrade-product-key-only

Upon booting the DVD, you will be asked for the key, so you will know if it works before the install begins.

http://www.howtogeek.com/169522/customize-your-windows-8-installation-disc-and-slipstream-updates-with-winreducer/

so from what you are saying, it is not possible to use my 8 Pro key to install 8.1 Pro? because you said I have to purchase another activation key?

the only way for me to get 8.1 Pro is to install 8 with my key then upgrade 8.1 ?

If your doing a clean install, your win 8 license key should work with the win 8.1 ISO found here:

http://windows.microsoft.com/en-us/windows-8/upgrade-product-key-only

Upon booting the DVD, you will be asked for the key, so you will know if it works before the install begins.

in this link, it says that I can not format my SDD HD first, does it mean I have to run it through first, then the file will make a DVD for 8.1 with my key built on it?

How about the Media Center? I used a separate key for WMC when MSFT promoted it for free last year.  If I clean install, would I get my WMC?

Thanks.

This site has two separate links, one for those with a Windows 8.1 key and the other for Windows 8 and each will only install the relevant O/S.

It is also the Upgrade option.

Keys are version specific and an 8 key will only authenticate a version 8 install.

"When you’re ready, tap or click Install Windows 8.1 if you have a Windows 8.1 product key, or tap or click Install Windows 8 if you have a Windows 8 product key. "

This site has two separate links, one for those with a Windows 8.1 key and the other for Windows 8 and each will only install the relevant O/S.

It is also the Upgrade option.

Keys are version specific and an 8 key will only authenticate a version 8 install.

"When you’re ready, tap or click Install Windows 8.1 if you have a Windows 8.1 product key, or tap or click Install Windows 8 if you have a Windows 8 product key. "