The site even had an online video and photo sharing service.
"Cloob.com was entirely blocked three times and the last time it took 28 days to unblock it," said company director Mohammad Javad Shakouri Moghadam in a blog post.
The website was able to fill the vacuum left by social media site Orkut after the government banned it, after several run-ins with the Iranian government cloob founder Moghadam decided to shut Iran's popular site.
However, sites such as Instagram are not banned and have boomed in Iran, while Russian entrepreneur Pavel Durov's messaging service "Telegram" has nearly 25 million users in the country.
"Cloob was one of the top three services in Iran but its flourishing tree has withered," said Shakouri.
"These days, some have started to... sue the new wave of content creators such as Aparat(a cloob product) and other services -- a source of domestic content creation which would definitely be of benefit to our country and culture," he told AFP.
President Hassan Rouhani was re-elected in May promising to soften social restrictions. He appointed Mohammad-Javad Azari Jahromi, to head the communications portfolio.
Jahromi had said that negotiations were underway to lift a ban on Twitter, though no progress has since been announced.
In 2013, the Iranian government had blocked YouTube, Facebook, Twitter and Google Plus in a huge Internet crackdown.
President Hassan Rouhani was re-elected in May promising to soften social restrictions. ||In 2013, the Iranian government had blocked YouTube, Facebook, Twitter and Google Plus in a huge Internet crackdown.