GPG error: http://..Release: The following signatures were invalid: NODATA 1 NODATA 2

PG error: http://mirrors.163.com trusty Release: The following signatures were invalid: NODATA 1 NODATA 2

首先将/etc/apt/sources.list中的源改为阿里源或者其它源，所有的http改成https，注意一定要https的源

然后报W: GPG error: http://mirrors.163.com precise-security Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key

原因是相应的KEY有问题

解决办法：更新所有KEY

sudo apt-get clean
cd /var/lib/apt
sudo mv lists lists.old
sudo mkdir -p lists/partial
sudo apt-get clean
sudo apt-get update

完美解决