Now is the time to sell shares of tech giant Microsoft , according to analysts at Guggenheim. The firm on Tuesday downgraded the shares to sell from neutral and introduced a $212 price target, implying a more than 11% downside for Microsoft. Microsoft may disappoint on upcoming earnings numbers in the second quarter of 2023 and in its full-year guidance as well. "While most investors see MSFT as a large stable business that can weather any storm, it does have vulnerabilities, some of which could be exacerbated by this macro slowdown," analyst John DiFucci wrote. Slowdown struggle could be ahead Microsoft has the greatest exposure to the small and medium-sized business market in Guggenheim's coverage, and SMBs tend to fare worse than enterprise companies during economic slowdowns, according to DiFucci. "In addition, Windows accounts for about 12% of revenue, but more than 20% of profit of the company, and while this business seemed like the Energizer Bunny during COVID, it seems to have moderated materially of late and this is expected to continue by industry analysts," said DiFucci. "CEO Satya Nadella's comments that 'the PC has never been more relevant to work, life, and play' on the F3Q22 conference call might be the visionary's first miscalculation after a long line of successes." Further weakness in Windows could impact cash flow numbers, Guggenheim said. The firm is also worried that Azure growth estimates for the second half of the year are at risk. The biggest headwind the firm sees is MPC business, where consensus numbers are expecting slight growth after several quarters of declines. "Separately, we're not the only ones concerned about MSFT's prospects over the near to midterm, as [Nadella] commented that it would be 2 years of challenges for the company, after which he expects MSFT to emerge as a stronger entity," said DiFucci. — CNBC's Michael Bloom contributed reporting.