SkyDrive won’t sign-on from my office.

I use SkyDrive to sync between my laptop and desktop.  Until last week it worked fine but on Friday last I noticed that it never completes the sign-in process when I am logged on at work.  All I get is the icon in my taskbar that indicates SkyDrive is signing in.  I took my laptop home and it worked just fine on my home network but again won't sign-in on the work network.  I checked with my work network administrator (who also uses SkyDrive) and he says it should work.

I am puzzled because it works on one network and not the other and also because it was working fine until very recently. I considered to uninstall/reinstall scenario but was afraid it would have an adverse affect on the files I have synced.