I use it with Clamwin-0.99.4 downloaded on his official site.

As it is the last version of Clamwin, I assume it uses the last version of Clamav too (0.103.1)

Clamwin-0.99.4 (released in March 2018) uses ClamAV 0.99, which is EOL and unsupported by ClamAV.

A sudden configuration change (due to excessive updates by some parties) on the ClamAV servers has broken updates for any EOL versions of ClamAV. (It's caught quite a few of us out!)

Clamwin needs to upgrade to a more recent version of ClamAV, or you can download a standard version of ClamAV and use the command-line options for scanning.

https://www.clamav.net/downloads#otherversions

-- 
Paul
Paul Smith Computer Services
support@pscs.co.uk - 01484 855800