how do I gain access to the command line?

[thorneo]

I have been trying to update to the latest version of opnsense but I get so far into it and it errors out saying and I quot " pkg-static: cached package clamav-1.2.0_1,1: missing or size mismatch, cannot continue
Consider running 'pkg update -f' "

So how do I do this command 'pkg update -f'

[Patrick M. Hausen]

Enable SSH in System > Settings > Administration > Secure Shell Server. Then use SSH to log on.

[CJ]

Before you do that, try changing your mirror and running an upgrade audit.  I think that will clear out any bad cached packages and let you perform the upgrade.