New router, cannot connect to certain servers! HELP ASAP please

[MacRae]

Hello and thank you for taking the time to read this,
So I've been using a vent server for awhile now and it's been working for me everytime, I've never had any problems with it. Two days ago I purchased and installed a new router. Now when I go to connect to this server (that I've never had any problems with until now) I cant get in. It will stay at "connecting to server" for roughly twenty seconds and then give me the same error message which reads

"Unable to connect to the specified server. Contact the server admin and verify that the server is online. You should also verify the hostname and port number with the server admin to assure that you are trying to connect to the correct server."

The server is still completely functional as other people are using it. I only get this problem from that server, I only use three servers, the other two I use are completely functional.

Im almost positive the problem lies somewhere within my new router and any changes that were made to my computer upon the router installation.
Also note:
-I haven't installed or changed anything with my firewall anti-virus etc etc.
-I've tried setting my IP address to static, no luck
-I've rebooted, re-installed, re-everything, no luck


Thanks for reading and taking the time to potentially offer some help,
-MacRae