When I try to use certain characters The update doesn’t work.
A few characters have special meanings, and need to be written differently. From the SDK documentation, you get:
< less than) <
> greater than) >
' single quote) '
" double quote) "
& ampersand) &
So the code you need looks like this:
QBObject1.ObjectType = "List"
QBObject1.ObjectName = "CustomerMsg"
QBObject1.AddProperty "Name", "Merry Christmas & a Happy New Year!"
QBObject1.Add