Cannot add a value to any variables by using the "="sign"

Hi every,
My VBA macro do not add a value to my variables This is my code:

Dim myVar As String
myVar = "HELLO"
MsgBox myVar
End Sub

It displays an empty Message box. I have debugged all other coding and it simply
ignores the "="sign

I hope you can help

Thank you in advance.

Dolly