The subscription(s) have been marked inactive ...

Very frequently transactional replications on servers send me the following error message:

Error Message : The subscription(s) have been marked inactive and must be reinitialized. NoSync subscriptions will need to be dropped and recreated.
Error Detail : The subscription(s) have been marked inactive and must be reinitialized. NoSync subscriptions
will need to be dropped and recreated. (Source: Server Name (Data source); Error number: 21074)

Even though "Subscriptions never expire" is marked.

I dont know the reason... Some said by default if nothing will replicate for 48 hours then it happened. some said a job that is responsible for mark subscription expired, if not run for specific time then it comes. but i dont get the xact reason and satisfactory answer but i got a cheat :)
Just go to distrubuition database and set the status of those publications to '2' and enjoy :)

USE distribution

Update [MSsubscriptions]
Set [status] = 2
where publisher_db = 'MarkedExpiredDB'

-- If anyone have better solution pls post.