Hi Tania,
I opened the link which you provided and downloaded SCMPluginDependenciesForEclipse4.4.0.zip file.
Once download completes then I am able to open/extract it with WinZip and WinRar. I guess file might not be downloaded completely. The SCMPluginDependenciesForEclipse4.4.0.zip file size should be 172MB. Please verify once again let me know if you get same error.
-Amar.