Chkdsk and external hdd with os question

[Thor_Odinson]

Will chkdsk have any ill-effects on c: if i ran it on an external hard drive containing the same os (xp sp3) and pretty much the same files as the aforementioned main drive? Basically the hdd in the enclosure used to be the former primary hdd of this pc. According to my friend, the volume kept getting dirty, so he replaced the whole thing entirely. He plans to use the old one as extra storage.

 

[corkyg]

Assuming that the external drive has a different letter, no effect at all on C. From the Command Prompt, CHKDSK runs on the specified drive only, and does only those things the switches tell it to.