anyway the fact is that i get the error DataTypes mismatch when 'm not sure it is not the case !!!

I have never seen VFP give a data type mismatch error when this is not the case < s >.

As i wrote before I got over it by selcting "Mytable" and set the index to 'MyIdx' before the seek. I don't know why but it works. As I told you is the very first time i got into this error...

Even if you select the alias and set the index, you are still not checking to see whether the record was found.

Anyway, you may want to check how the value property of the text box is initialized. If the data type of the ControlSource is anything other than logical, you need to initialize it in the propery sheet as either 0 (numeric, integer, etc.), {} (date), {/:} (datetime), or an empty string (character).