Version number not updating

It is just me or is the version number for calibre stuck on 4.13. After trying to update to 4.14, calibre's version reads 4.13 but it's actually 4.14 with the features from "What's new". Now, after updating to 4.15, the version number is still 4.13.

Because of this, the "Update found" is always appearing.
I'm on windows 7 64 bit. I know you guys say windows 7 is broken but everything works for me so far. It's just the version number is not updating.