SDK Files

Upon a recent review of my computer’s hard drive (running Windows XP), I noticed two sdk files (sdk.n and sdk.m). But, I do not know where these files were installed from and noticed that they are each 2.3 gigs (sapping a lot of room off of my drive).

First, should I be concerned about these files and, two, what can I do to recover the room they are taking up (eg, can they be safely deleted)?

Thank you in advance.

deputac