Fatally Missing Blocks and Items Error

[Namelesswon]

Is anyone else having this issue when connecting to FTB Infinity Evolved?
I am hosting my own server. First time ever doing this, and my friends who are playing with me are able to connect to the server with no problem. I am unable ;n;

Please someone help explain what I should do to fix this asap. thank you!

 

[Quetzi]

Make sure you are using the same configs on both the server and client. Also, be sure to check our support area above.