John Chen, BlackBerry's interim CEO, aimed Monday to reassure his company's enterprise customers in an open letterJohn Chen, CEO, BlackBerry

Echoing a similar letter sent to customers back in October, Chen reiterated the message that BlackBerry isn't going anywhere and that customer investment in BlackBerry infrastructure and solutions are secure. 

In the letter, Chen focused mainly on BlackBerry's device management efforts, noting the company's platform now supports multiple operating systems, namely iOS and Android. 

Chen also acknowledged that BlackBerry has a lot of work to do to regain its footing. 

"I know that it’s going to take time, discipline and tough decisions to reclaim BlackBerry’s success and we are ready for that challenge," Chen wrote. 

Back in October, BlackBerry published a letter that touched on similar points. That letter boasted BlackBerry's "substantial cash on hand" and a balance sheet that is debt free, as well as cost-cutting measures that the company claims will reduce expenses by 50 percent.

In early November, BlackBerry ousted CEO Thorsten Heins, saying it was abandoning plans to go private, and would instead seek to raise $1 billion in funding.