Live Mail 2012 not downloading all messages

I've used Windows Live Mail 2012 for many years. for some time now with problems downloading messages from my email server Tiscali/TalkTalk.  This is getting slowly worse, and it is rare I can send messages and see them immediately in my sent items, likewise downloading messages to my inbox

Some messages in sent items and inbox are downloaded some not.

Frequently the program freezes and tells me that my server refused to accept/various other reasons

I have no problems at all finding my email messages in the TALK TALK webmail account

Would be grateful for a fix if at all possible