In November, the smartphone firm said it would exit the country after it received an official demand for access to the data.
Pakistan's telecoms regulator had said it wanted the messages to help it fight terrorism and crime.
Now, the Pakistani authorities have dropped their demand.
The original request to see emails and other messages sent via Blackberry phones was made in July. Pakistan wanted access to encryption systems that scramble the messages making them hard to read.
It gave Blackberry until the end of November to comply, warning the firm that it would no longer be allowed to operate in the country if it declined.
That deadline was subsequently extended until 30 December by Pakistan's Telecommunication Authority.
Now, said Blackberry boss Marty Beard in a blog, the demand for access has been dropped entirely.
"After productive discussions, the government of Pakistan has rescinded its shutdown order, and Blackberry has decided to remain in the Pakistan market," wrote Mr Beard.
He said the company was "grateful" to the government and telecoms regulator for accepting Blackberry's assertion that it could not read the messages people sent nor give access to the servers behind its messaging system.
In an earlier blog setting out his position, Mr Beard said the company was happy to work with the police on specific cases but it would not give blanket access.
Industry figures gathered by analyst company IDC suggest that, in early 2015, Blackberry had a 0.5% share of the global smartphone market.
In 2014, Blackberry shipped about 5.8 million handsets - 70% fewer than in 2013.
Blackberry is no longer going to shut down its operations in Pakistan as it has resolved a row concerning its users' messages.