Onedrive aka skydrive, backup-updates and the store are 3 optional Microsoft services that a computer can sink (make a semi-permanent connection) too, Microsoft wants you to use these because they know people tend to use only one such database and they want to own it but the point is that this database keeps a copy of your account.
You can un-sink (remove yourself from this database) from within windows BEFORE un-installing and as you just witnessed that is simpler than trying to do it from the outside.
Happy to hear you have it sorted.