try using the ascii character map, ie chr(65) is A
find the table below
http://www.asciitable.com/
then use then randomize, and then the rand command to be able to pick a random character between the range that you require.
By memory it is rand(high-low)-low
try the below. (there might be a couple of errors as I haven't done VBA for a while)
randomize
randomcharacter = rand(90 -65)-65
range("A1") = chr(randomcharacter)
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