A rising star at Microsoft says employees sent him hate mail for suggesting the company might be falling behind

When Microsoft bought tiny startup Acompli in 2014, it didn't just get the app that would become Outlook for iPhone and Android - it got Javier Soltero, the former Acompli CEO who's now one of Microsoft's biggest agents of internal cultural change.

At Microsoft, Soltero has worked to bring a more Silicon Valley mentality of adding new features and iterating on apps quickly, making him a key player in CEO Satya Nadella's overall master plan to reform the company's culture to stay relevant in the post-iPhone world.

Not everyone at Microsoft is so receptive to that message, though. In an interview with the Wall Street Journal's Jay Greene, Soltero says that sometimes, his new colleagues at the company just wouldn't accept that Microsoft needs to stay strategically nimble or risk falling behind.

About a year after joining Microsoft, Soltero tells the Journal, he gave an internal presentation warning that Microsoft was resting on its laurels in the e-mail space, and that an increasing number of customers were moving away from its Exchange and Outlook programs and into web equivalents, like Google's G Suite.

Soltero warned that without drastic action to improve its own e-mail products, Microsoft could slide into irrelevancy, like Lotus Notes - once a major player in corporate e-mail software, but now a footnote to history.

At least some employees were non-receptive. Soltero says he got internal e-mails accusing him of being "disrespectful of the legacy" of Microsoft and its e-mail business.

"I think the suggestion that we weren't winning was a painful one for them to hear," Soltero told the Wall Street Journal.

Soltero is a rising star at Microsoft: While he was originally tasked with leading Outlook on mobile devices, it took less than a year before he was put in overall charge of Outlook on all platforms. In November, he was promoted to oversee strategy for Microsoft Office overall.

In general, and as the Wall Street Journal reports in a broader sense, Nadella and his executive team have turned to the talent that Microsoft has gotten from acquisitions to bring an outside voice to insider decision making. An as part of that effort, Microsoft has been pushing talent like Soltero up through the ranks faster than usual.

Read the full Wall Street Journal report here >>