The Windows 11 Pro activation key I received didn't work at first. But after I contacted the company, they sent me a new key, and now the system works perfectly. I recommend this company to everyone.
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Quick and efficient experience. I payed for my key and it worked correctly. I've had times where other companies have sold me keys and they don't work and they won't respond.
Apparently the codes they sell are almost always "in use". I e-mailed the support and they never bothered to answer back. There are easier and cheaper ways to activate your Windows, don't waste your m... See more
The first license didn't worked, but they've responded promptly when I asked for a replacement, and gave me another one, which works!
Company details
Written by the company
At operacinesistema.lt, we make buying operating systems safe and simple. We provide legitimate Windows 10, Windows 11 Pro operating systems for individuals and businesses. We offer full support, warranties, and physical installation media (USB) as well as digital windows keys to ensure your PC runs smoothly and securely.
Contact info
Lithuania
- operacinesistema.lt
4.0
Great
39 reviews
Replied to 83% of negative reviews
Typically replies within 24 hours
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Used codes, lazy support.
Apparently the codes they sell are almost always "in use". I e-mailed the support and they never bothered to answer back. There are easier and cheaper ways to activate your Windows, don't waste your money on these guys.
April 15, 2026
Unprompted review
Instant response
Instant response. Received exactly what was ordered.
February 26, 2026
Unprompted review
All good and working
January 1, 2026
Unprompted review
This company is a SCAM. AVOID IT.
Unfortunately I could not give zero stars as zero is what I got from them for my money.
I bought a Windows 11 key from them but when I tried to use it, Microsoft indicated that it was "already used".
I complained by e-mail and got a quick response (positive!) with a new key. Still "already used". I repeated my complaint several times and always got another key that was always invalid (already used).
Then I asked for my money back and just got anotehr key that does not work.
Be warned: This is a SCAM and you should avoid dealing with such people at all cost.
April 12, 2026
Reply from Operacinesistema
Hello,
I apologize for the inconvenience caused, although there is no way to check whether a key is valid or not, in your case there may have been external factors which made an impact to the success rate of the Windows 11 Pro activation and we were ready to give you unlimited replacements untilt he key works. If you wish to activate your Windows 11 Pro, contact us at help@operacinesistema.lt
Good and fast service
April 12, 2026
Unprompted review
The key was fake and was already in use…
The key was fake and was already in use so its just not worth it
April 10, 2026
Reply from Operacinesistema
Hello,
I apologize for the inconvenience caused, although I did not see any emails from you regarding replacement or refund. If you wish to resolve this matter, please contact us at help@operacinesistema.lt
Becouse got the code from second time.
April 8, 2026
I buyed a Windows 11 key It was fake
April 2, 2026
Reply from Operacinesistema
Hello,
I apologize for the inconvenience caused, although I did not see any emails from you regarding replacement or refund. If you wish to resolve this matter, please contact us at help@operacinesistema.lt
The purchased product does
The Windows 11 Pro activation key I received didn't work at first. But after I contacted the company, they sent me a new key, and now the system works perfectly. I recommend this company to everyone.
April 2, 2026
Worked perfectly!
February 15, 2026
Unprompted review
Promptly license replacement
The first license didn't worked, but they've responded promptly when I asked for a replacement, and gave me another one, which works!
March 12, 2026
Unprompted review
Good payment options and the fact that…
Good payment options and the fact that it came in seconds
March 17, 2026
Unprompted review
The key is working properly
March 12, 2026
Unprompted review
Quick and efficient experience
Quick and efficient experience. I payed for my key and it worked correctly. I've had times where other companies have sold me keys and they don't work and they won't respond.
March 12, 2026
Unprompted review
Helpful guy
Helpful guy. He really does a lot to satisfy customers request.
March 2, 2026
Unprompted review
Great work.
February 13, 2026
Unprompted review
Works great so far
Works great so far, been about a month and no issues at all.
February 23, 2026
Unprompted review
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