Can't install any packages

[eddy89]

Hi,

I am unable to install any packages at all. Here is the out put of the install.

ERROR: Invalid digital signature! If you are *SURE* you trust this PBI, re-install with --no-checksig option.
of nmap-6.47-amd64 failed!

Any help on this?

[jimp]

Check that there is not a proxy or other source of interference between the firewall and the Internet. Typically when that happens it's on internal firewalls with something else ahead of them like a web filter, proxy, or other portal that prevents downloading the file as expected. Either that, or the file is being pulled from an unofficial repository where the package hasn't been properly signed.