itunes freezes on windows 10

You could try sending Apple some feedback, using their Feedback form: https://www.apple.com/feedback/itunesapp.html

Note though, that Apple do not reply to your feedback and it is up to them whether they fix the problem. (I wouldn't hold your breath.)

While it's in that frozen condition on startup, do you see an additional icon in the top right of the iTunes window?

Check for it the next day that you start up iTunes.

If you re-start iTunes on the same day, the icon may be there for such a short time that you miss it. Hence the reason I suggest testing this the next day.

I realise that.

I'm asking because whenever I start my iTunes, I get that icon in the top right (as shown in the screenshot) and my iTunes is frozen (and useless) and I thought that this might be what's happening to you too.

On the odd occasion that I've been quick enough, I've managed to click on View / Show Activity Window before iTunes actually freezes and in the pop-up window that appears, it tells me that iTunes is "making my purchases available".

I don't think I'm being unreasonable in thinking that it shouldn't be necessary for iTunes to check this every time that I start it and to make itself totally unusable to the customer (that's me) until it's finished.

Since I haven't managed to find a way to prevent iTunes from indulging in this navel gazing I simply put up with it, but it's extremely annoying.

The cloud thing is to the lower right of the activity indicator in my screenshot. I don't use the cloud, so no idea why that should appear. I'm fairly certain that the making purchases available is the cause of the freeze.

As for my "purchases"; I have fourteen songs in my Library that came from the iTunes Store - and at least twelve of them were given to me by the store without their bothering to ask me if I wanted them. To be honest, I don't recall buying the remaining two.