Are you trying to save to a local drive? or are you trying to save to a networked drive?
Does this occur with all InDesign CC files? Or just one particular file?
What happens if you create a New InDesign document and try to save it into your Documents folder.
Are you on Mac or PC? Try checking permissions for directories in which you are saving, or on Mac fixing permissions errors (Disk Utility).
Also if the problem occurs for all files. Try renaming the InDesign preferences folder and clearing caches. See http://helpx.adobe.com/indesign/kb/indesign-preferences-support-file-locations.html for more information about this.
Also - If this doesn't work and it's only on one particular file try saving the file as InDesign IDML, then open the .IDML file in InDesign and once it's fully opened try saving that as InDesign file again.
If its the same problem whrein Save/SaveAs and undo/redo gets disabled, then the workaround as of now is to export the file to .idml and then open the .idml. This way you would be able to save your work. We are aware of this issue and you would get this fixed in the next InDesign CC update.
When I removed a placed inDesign from the file is then saved, I then exported the placed Indesign file as a pdf and placed it back into the InDesign file.
Note to myself DON'T PLACE INDESIGN FILES INTO INDESIGN FILES.
Yes tried this, it still wouldn't save.