Windows Defender Antivirus detected Laroux Virus but I can't get rid of it with Windows Security

[SteveDavidC]

I was copying some files from old discs onto my laptop but seemingly one contained the Laroux virus. Windows Security describes the threat as Severe and offers 4 options (Clean threat, Quarantine, Remove, Allow on Device). I haven't pressed 'Allow on Device' but I have tried the other three but all to no effect.
The Status tells me 'Active threats have not been remediated and are running on your device'.

Any suggestions as to how to rid my laptop of the virus would be welcome.

Thanks in advance.

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