Hi All, our network infastructure is on IP-VPN. Every remote site has their own router (Linksys), and at HO we have cisco router too. HO -> router (cisco) -> private network -> router (Linsys) -> remote site. the other remote sites are fine as usual (ping, access etc) but only 2 sites we cannot ping/ or access to those 2 routers but interestingly we're still able access (RDP, Ping etc) inside those 2 remote sites, and ping/ access to those 2 routers within the remote site's network NOT from HO, I hope it is not confusing. So what I have done is that checked Cisco router, checked Linksys, check anti-virus, firewall... everything seems in order. have I missed anything? Thanks in advance

If you are trying get get packets back and forth between the HO and remote office, accordingy to your diagram you have two routers in between. The two routers will need to have the far side of each others networks in their routing table. Visit: anITKB.com, an IT Knowledge Base.