The error 5 when calling TextStream.WriteLine is typically caused by trying to write data the TextStream can't encode:
Trying to write "U+1F00 ? e1 bc 80 GREEK SMALL LETTER ALPHA WITH PSILI" to a stream opened with/for 'ASCII' encoding:
>> Set f = goFS.CreateTextFile(".mp.txt")
>> f.WriteLine "A?"
>> --- no news here means: written ---
>> f.WriteLine ChrW(&H1F00)
>>
Error Number: 5
Error Description: Invalid procedure call or argument
To prove this:
>> f.close
>> Set f = goFS.CreateTextFile(".mp.txt", True, True) ' overwrite, unicode
>> f.WriteLine ChrW(&H1F00)
>>
>> --- no news are good news --
As the data source (.ReadAll()) seems to come from the WWW, it's probable that it contains non ASCII/ANSI text. Be warned though, just opening the output file for Unicode (=UTF-16) won't help if the input is UTF-8 slurped by .ReadAll() on a ASCII Textstream.
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