The unusual occurrence related to IM Shield, Skype and Dropbox

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While using Skype, I noticed that every time IM Shield scan some file at the following address:

C:\Users\Username\AppData\Roaming\Dropbox\shellext\5202b8cd

I find this strange. Does Skype access to my Dropbox folder? Is this normal? I am worried. My Computer is clean and the Skype is just installed.

Thanks and forgive me because not so good English.