Validation Rules for multiple fileds

[truebluecutie]

hello, i am super duper new... and am working on a school assignment for weeks! its due tomorrow but i cant get this one rule to work... please help if you can!!
Basically I am trying to add a validation rule to a field refering to a different field in a different table.
Both fields are Date/Time type
I am new.. and not as advanced as some of you.... so maybe walk me through it?? i have spend many hours trying to figure it out~ thanks

 

[M8KWR]

if you could tell us what exactly you are trying to achieve, and why you need to do this.

There could be different solution, but for us to find to the best one that suits your needs, we need as much info as possible.

If you could also let us know what the tables and field names are called it would hopefully save you having to alter code that we may post here.