Simply download the lastest firmware from the product's page and install it manually using Dfuse, as explained in the link posted above.
Also download and install the last PC software (v1.1.12), it looks like Hantek fixed the autoupdate in this version of the software. Well, at least I didn't have this kind of problem anymore after the update.
Please scan the QR code on the back of the oscilloscope to download the software and install.
Now run the software and click "Help->Checkupdate" to open HT2xxAutoUpdate. Now select "Rescue" and operate as prompted.
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