In an SQL database I have a field called Termination Date that is populated with 9999-12-31 for employees that have not been terminated. I'm trying to create a formula that would put a blank in the crystal report field if the termination date is 9999-12-31 otherwise I would use the termination date.

A couple of things that I noticed. 9999-12-31 is not a date (in fact I think CR would translate it as a expression).  I am not sure that if you used the date function that is would translate it properly.  Two you cannot assign value to a field, but you might be able to do the following.

In an SQL database I have a field called Termination Date that is populated with 9999-12-31 for employees that have not been terminated. I'm trying to create a formula that would put a blank in the crystal report field if the termination date is 9999-12-31 otherwise I would use the termination date.

if totext({dt_Employee_Client.Termination_Date},"yyyy-mm-dd" = "9999-12-31"
then  '  '
else {dt_Employee_Client.Termination_Date}

Also I should mention the equals sign is an comparison operator, colon equals (:=) is the assignment operator.