In addition. If you want to try a repair of Office then that should be simple enough. Open Apps and Features and search for office (depending on the version) select Advanced options and select Modify > Repair, or Advanced options then Repair.
I would only think it could be something to do with the size of the file (there is a restriction from your email provider about attachment size) but then again the files you shared were only very small so you should have been able to attach and send both of those.