Block was widely seen as a potential successor to Benioff, who founded the company in 1999, and will continue as the chairman.
The company has spent more than $16 billion last year for acquisitions, adding muscle to its cloud products as it fends off competition from bigger rivals like Oracle Corp and German competitor SAP.
Salesforce forecast first-quarter revenue between $4.88 billion and $4.89 billion, compared with analysts' estimates of $4.84 billion, according to IBES data from Refinitiv.
The company reported a net loss of $248 million, or 28 cents per share, for the quarter ended Jan. 31, compared with a net income of $362 million, or 46 cents per share, a year earlier.
On an adjusted basis, the company earned 66 cents per share, beating estimates of 56 cents per share.
The company's total revenue rose 34.6% to $4.85 billion, above estimates of $4.75 billion.
(Reporting by Neha Malara in Bengaluru; Editing by Shailesh Kuber and Shounak Dasgupta)
