古村 光夫 We will be pleased to help you with this problem so have logged a support case on your behalf. You will be contacted at the email address used for this Community. Support Case Id : 00659372 .

I posted the email below.
After trying many times after that, I was able to resolve the issue voluntarily.
The contents are as follows.

I went into my account at Trados Live (languagecloud.sdl.com) and clicked on "Connected Devices".
When I checked the contents, I found that one desktop and two web browsers (Chrome) was active.
So I deleted all three of them.
Next, I clicked on the subscription license confirmation button that appeared when starting Trados 2021, and Trados 2021, which had stopped starting and completed all its operations, started normally.
This was the only thing I did, but it took me two whole days to find it.
I hope this will be helpful.

Mitsuo KOMURA
Japan

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The "reset license" has already been done when I purchased the "Trados Studio Freelance L1 - 12 month subscription".
If I did not "reset license" SDL Trados Studio 2011 Freelance Plus, I would not use the "subscription license" for Trados Studio 2021!
So, it is impossible to reset license again.
I want a reset or recovery procedure for my subscription license, not a reset procedure for my former permanent license.

question was
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I was using Trados 2011 Freelance plus (perpetual license) on windows 8.1.
Last October, I purchased a subscription (1 license) for trados2021 and was using it.
On the 6th of February, I upgraded from windows 8.1 to windows 10.
After that, when I try to use Trados2021, the message "Cannot start because the available limit has been reached" appears, and I have failed to start Trados2021 many times.
I hope that you (RWS) will take the necessary measures (resetting the license, etc.) so that I can use Trados 2021 on my PC.
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answer was
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Here is the link to reset your Trados License.
gateway.sdl.com/liveagentlicensing

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