My SkyDrive indicates that it is full although it has 27 GB of space and  contains only 10 GB of documents and one two GB picture that I was able to transfer by hand.  Every file has a red x on it and it is not updating files as I edit them on my computer.  The only files in SkyDrive are the ones I first loaded, but then I only had seven GB and I had an insufficient space warning at that time.  I have not compared my computer files with the SKYDrive files so I have no idea whether all my files transferred.  I then added 20 GB memory, but  I still get the insufficient space warning.  It would be great to have a notice about how much space I need.  I don't understand my problem but I don't understand the answer provided to the original question because it isn't an answer.  Isn't there some way to explain a process in simple terms?

I note that I was able to drag one file to SkyDrive to insert a new version of an existing file.  I was also able to copy a picture to my pictures folder (which otherwise contains no pictures).  Both new files have red x's.