I think it should be good practice everywhere users upload something, to try to download it once afterwards. Then the user would've seen that something must have gone wrong.
here, here... I have just had this problem with the syncgrain~ external I was whinging about all last week. The ~ was missing in the .dll file I downloaded (from www.audionerd.com) and therefore wasn't working. I know this is undoubtedly very obvious to more seasoned pders but for someone still cluelessly weaning themselves off commercial software it's not; even if it were, mucking about with files that one assumes to be 'in order' is normally not advisable as the chances of wreaking even more havoc are high... The 'download once test' would save a lot of hair-tearing and would probably also result in less people like myself clogging up the mailing list with irratating questions!
L