Have you used Connection Doctor ( in Mail go to the menu item 'Window' and in the drop down select 'Connection Doctor'. It will test you connection and if you have the program display the connection print out then you can see what the server is replying to your Mac. This way you can trace down if it is an OS X problem or setting problem.
yep through FF, i like it this way, sometimes messages send , other times says the error message, but messages are in the sent folder.. so they do seem to go.. why is it like that? will it write itself?
Seems like we're just going around in circles.
If the problem is on Hotmail's end, then, yes, you can expect it to start working reliably again (although that seems a little contradictory by my past experience with Hotmail, not the best email service in the world, eh?) The only folks that can really tell you 'why does it do that?' would be the folks at Hotmail.
When you access a service via the Web, then any problem on your end will always be there. Intermittent problems are almost always the exclusive domain of the server and its owners. In this case, that is Microsoft. There is absolutely positively nothing that anyone on this forum can do to fix a Microsoft problem.