Clamwin are forcing signature file update to be version controlled. This is problematic for the current version of clamwin here. I have successfully manually updated using the process described here https://portableapps.com/support/portable_app#upgrading, replace the bin and lib folders under \liberkey\Apps\Clamwin\app\Clamwin or your Liberkey and perform the update successfully for the current set of signature files.

I have also sited but cannot relocate a suggestion to download the 32-bit 0.103.0 version [correction] https://oss.netfarm.it/clamav/