Hi,
Well, Microsoft bought Skype back in May 2011, over 5 years ago, so that's quite old news. It's unlikely you had problems this recently due to that switchover. It's more likely that you had a problem with using different types of accounts in W10 and that's causing the issue with your MS account. Also, you posted your problem in the W10 forum here, does that mean that all 3 of your computers have W10 on them? Or do you have a mix of computers with different versions of windows, such as 1-W10, 1-W8.1, 1-W7? It would be helpful to know that.
More importantly, you need to understand the difference between a Local Login Account in W10 and a Microsoft Account Login in W10. The main difference is, that with a Local Login, you use whatever account you want to login to W10 with no associated E-mail address. Such as
"FRED JONES" and a password. You can still get to your W10 desktop, programs, data, and even to your Internet.
HOWEVER, and this is a big however, with a Microsoft Account login which you would have to had associated with an E-mail address and password that's actively working when you setup 1 or more of your computers, this allows access to your computer as the Local Login account does as just described, but in
ADDITION, you would then have complete access to the Microsoft Universe, primarily their App Store to purchase or download media content in the Microsoft Apps Store such as music, movies, and Xbox games, etc.
If you had to change the E-mail address on your Microsoft Account login as you described due to an ISP change, you would need to go to the Manage Account option once logged into your Microsoft Account on at least 1 of those 3 computers you have, and preferably using a computer that had W10 on it. This is just as neemobeer suggested to you in his Post above. So, if your old Microsoft account had an E-mail address of
fredjones@OLDISP.com for example, you would need to
CHANGE your primary E-mail account in your Microsoft account seetings to your new ISP E-mail address; for example:
fredjones@NEWISP.com.
Once this is done, you should then be able to login to your Microsoft account with your new Microsoft Account from any of your 3 computers, regardless of which ones or even all 3 of them have W10 on them!
Further, you need to check your new ISP E-mail address and verify that it is working, and you can log into it from a browser on all of your computers. Microsoft will send you a verification E-mail request to that new E-mail address, and you must go into your Microsoft account from one of your computers and click on the verification link. If you do not do this, your new E-mail address will show
UNVERIFIED next to it in your Microsoft account settings, and things won't work properly such as syncing between W10 accounts, and
NO ability to purchase/download things from the Microsoft store.
This will also include the ability to use your Skype account--until you complete this verification process of your new E-mail address. If for any reason you don't have that new E-mail address from your new ISP yet, or you didn't go through the verification process, you'll continue to get error messages on all 3 computers you own, and any other computers you use such as a friend's, co-worker's, library computer, etc. The Microsoft tech you had really didn't know networking nor how W10 Accounts work, he probably assumed you already knew it, or simply couldn't explain it to you. This entire Local Account vs. Microsoft Account thing is
COMPLETELY NEW TO W10! Most folks don't understand it unless you have experience working in a corporate business network where they have you use a network Domain login to access corporate resources on their network--the W10 account login paradigm is very similar.
Now that you understand the difference between Local Accounts and Microsoft Accounts in W10--this will be easier for you to fix. At this point, when you switch back to Local Accounts on all your W10 computers as neem suggests, and you've verified your Microsoft Account works with a browser to login manually to your account on at least 1 of your W10 computers, you
MUST then switch over any other W10 computers you have. If you have 2-W10 computers for example, you have to switch both of them to Local Logins and access the Internet with them and verify you can do this.
If you have all 3 of your computers that are W10; you must do this with all 3 computers. Quite simple, really. Once you have done that, you then simply choose your W10 computer, or one of your W10 computers if you have more than 1; and login into it using the local login as you would need to create on all your W10 computers as above; for example, the
FREDJONES account example above. You then go into W10 settings and switch your login type back to Microsoft Account login, it will reboot your W10 PC and you can then use your browser to confirm your Internet connection, and even go into the Microsoft store. At that point, I would immediately go to the MS App Store and purchase a low-cost item like an old music album or movie say $10 or less. Make sure it processes your credit card, download the media and play it. If it works, everything including your new E-mail address on your Microsoft Account Login is now working and you're good to go on any and all other W10 computers!
Here comes the difficult part; if you have any of the other 2 computers also running W10, you'll have to repeat the process I described in the paragraph above--which is a more detailed explanation of what neem suggested you do in his Post. If either or both of your other 2 computers fail to work as the first W10 computer did then those W10 computers are borked and must be repaired or replaced!
Most likely, they have become corrupted, or infected by a virus/malware, or suffered a hardware failure such as bad RAM stick(s) or faulty Hard Drive.
You will need to apply Hardware testing to each of them, and probably do W10 Clean Installs on them or reinstall completely using Factory Recovery Media (DVD or USB). If you don't have W10 install media, you can download the free MCT tool from Microsoft here:
Link Removed
If you can't get that to work, and you don't have or can't create factory Recovery Media for your computer(s), you can buy it directly from the computer maker for
$29-$99 US and then reinstall your W10 on your computer(s).
P.S. When you are testing your first W10 on your newly verified Microsoft Account Login, it would be a good idea for you to test your Skype Account to see if it still works or not on that first W10 computer. If it does, you're good to go with Skype. Remember, to test Skype on each of your other W10 computers as well to make sure it works on those too. If it doesn't, there is probably something borked on that other computer(s) and they may have to be rebuilt as above.
Finally, if you don't have experience rebuilding computers from scratch and reinstalling W10 OS, you might want to consider taking them to your local licensed Computer Pro and paying him to do it for you.
Best of luck,
Let us know how it goes or if you have any questions.
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