quote "...they can be safely deleted, but I'd advise only deleting old ones that you know is a stable hotfix..."

1.How do i know that it is a stable hotfix?

2."....Those Windows Updates are simply replacing existing Windows files for the most part, so the amount of drive space remains more or less constant...."

So i don't need to delete the windows updates at all then, since the new ones will replace the old files.

3.When you said it'll occasionally cause problem, does it mean soon or later it'll cause problem or it might/might not cause problem? and what kind of problem is that, you mean like it may cause file system to corrupt? and

4.how do i know which one to delete when this problem arises?

cheers