[RESOLVED] I can't opearte a simple + command...?

[opus]

Because you are "adding" Strings! You have your decimal values from database, however you put into textboxes (which hold text, or strings).
You have to Re-convert the text to a number, or even better use the original number for the addition!
The Re-Convert would look like that:

TextBoxAnswer.Text = CDbl(TextBox1.Text) + CDbl(TextBox2.Text) + CDbl(TextBox3.Text) + CDbl(TextBox4.Text)