–Machine translation added by Dolbyman–
Hi, I have a QNAP TS-251D
with 5.2.6.3195
Admin is disabled, but I can no longer log in with my account password.
I tried the reset button, but it doesn’t work. Can anyone help me? Thanks.
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Hi, I have a QNAP TS-251D
with 5.2.6.3195
Admin is disabled, but I can no longer log in with my account password.
I tried the reset button but it doesn’t work, can anyone help me? Thanks
Hello,
How do I reset my NAS
How do I reset my NAS settings? | QNAP
What is the default system administrator password for my NAS? | QNAP
Username: admin
Password: The Cloud Key of your device, password is Q12345678
It depends on the firmware version as the link you provided indicates. There are other password options.
Please only post in English, in this English forum section
He has a TS-251D with QTS 5.2.6.3195
Very true. Just making it clear for any future readers of this. Although, this topic is covered many times and nobody seems to find the info on their own 
Also worth mentioning that many older unit do not have the sticker with the “cloudkey” number on it. If that info isn’t available, some members, and of course QNAP support, can provide it based off the MAC address. If you don’t have the sticker, you may want to run QFinder on your own, on a system you can access, and make your own note in case you need it down the road.