I have an old HTC Sense and i am having problems getting market to open or even updating to google play store.
"Android Market" has been renamed to "Google Play Store" long ago. Afraid Google also changed the API since and deprecated the old one, so you won't be able to use this "ancient" version anymore.

For an alternative, you could try F-Droid, an open source Android "market" which should still work with "ancient versions". There you'd also find apps like Yalp Store, which would allow you accessing Play Store.