Download guam-0.9.5-4.3.el7.kolab_16.x86_64.rpm & erlang-eimap-0.4.0-10.3.el7.kolab_16.x86_64.rpm
systemctl stop guam
cp /etc/guam/sys.config /etc/guam/sys.config.save
rpm --nodeps -ehv guam-0.9.8-1.3.el7.kolab_16.x86_64
rpm --nodeps -ehv erlang-eimap-0.4.3-1.2.el7.kolab_16.x86_64
rpm --nodeps -Uhv guam-0.9.5-4.3.el7.kolab_16.x86_64.rpm
rpm --nodeps -Uhv erlang-eimap-0.4.0-10.3.el7.kolab_16.x86_64.rpm
cp /etc/guam/sys.config.save /etc/guam/sys.config
systemctl enable guam
systemctl start guam