i think part of the strangeness that rootboy's referring to is that, while it is true that mirc won't /write to global.any_extension - if you do:

/write global.hash.txt test

you can go out to win-explorer and see that the file actually *DID* get created. However 6.34 tells you that

//echo -a $isfile(global.hash.txt)

is $false instead of $true

Perhaps $isfile is parsing the filename differently than /write is.

In case it helps track down the peculiarity, 6.32, 6.33 and 6.34 all allow writing to global.hash.txt, but 6.33 incorrectly gave a false message that it failed to write to the file, even though all 3 versions can.