Can I write a character on the specified location of a string*255

If it can happen then do reply soon cause
now I am in the final stages.

I am waiting on the line for the next half an
hour.

If you can, please give a small example as well.

A problem stays like a challenge till
I find the solution to it.

here is a sample

Dim stra as string
stra = "this is a test"
mid(stra, 5, 1) = "f" ' write to position 5
MsgBox stra

BTW if you still work on the GetShortPathname stuff,
the return value from GetShortpathname is the number of characters copied into the strShort buffer.
if you need only the relevant characters:
l = getshortpathname( strLong, strShort..)
strTrueName = left( strShort, l) ' get's only the relevant characters from your string