Microsoft Outlook went dark on Rita Elkazzi just as a volatile week in markets was coming to an end. As swings in AI stocks and bonds kept traders on edge, the UBS Group AG execution-sales head for Australia and New Zealand was forced onto phones and alternative channels to communicate.

Microsoft shares fell 0.4% in extended trading following the disruption, which affected access to several of the company's services.“It’s been a bit of a disaster and I can’t believe still not resolved,” said Sydney-based Elkazzi. “It means a lot more diligence on ensuring trade recaps et cetera are accurate.”Elkazzi’s experience is echoed by many after Microsoft Corp. suffered one of its most severe disruptions in recent memory. The tech giant is still struggling to restore access to some of its flagship software hours after an outage began, affecting its Outlook, Teams and Copilot systems.

The difficulties in communicating efficiently have hindered workflows on trading desks, delayed corporate disclosure and even affected email access for Japan’s Ministry of Finance.Also read: Microsoft outage LIVE updates: 15 hours on, fixes not working 'as expected', tech giant scrambles to restore servicesIn Singapore, traders reported some banks’ inability to complete financing deals. Meanwhile, a few Indian brokerages sent out alerts to the potential impact on their services, with IIFL Capital Services informing their clients that there could be a delay in responding to emailed queries.Australia’s main exchange operator ASX Ltd. told customers it’s aware of an issue affecting some Microsoft 365 services including email, adding that the bourse’s services remain available for normal operation.

Workhorse Group Inc., a US truck and bus manufacturer, said it would postpone its earnings release. In Japan, the government’s shared IT platform also experienced disruptions, with the finance ministry saying it can’t receive emails due to the outage.

Among those affected is Calvin Yeoh. The portfolio manager at hedge fund Blue Edge Advisors said he can’t check emails and is struggling to access brokerage reports and some trading platforms that require email authentication.“Outlook is the appendix of the modern financial operations world,” said Yeoh. “So aside from the entire front to back infrastructure of global finance being crippled, and with Nvidia melting down and rates markets going wild this week, yeah it’s been all good.”Also read: Microsoft gives initial explanation for outage; says ‘servers were unexpectedly unavailable’Meanwhile, CMC Markets traders are resorting to “old-school” trading as Microsoft’s systems went offline. “Everyone was back on the phone, and our WhatsApp chats were busier than usual,” said Eugene Koh, sales trader at CMC Markets Singapore. “Something that normally takes a second on email might now take a phone call and a few minutes to get through.”Similarly, Ryutaro Kimura, a Tokyo-based senior bond strategist at BNP Paribas Asset Management, said while trading itself is largely unaffected, “confirmations backed up, creating settlement headaches for back offices.” “Desks were still getting trades done by phone and fax,” he added.The outage has attracted about 200,000 reports of user issues across Microsoft services on Downdetector, ranking among the company’s most severe.

Previous disruptions have rarely lasted more than several hours. Microsoft shares were down 0.4% in extended trading.After initially struggling to identify the issue and test potential remedies, the company said in an update that it’s “seeing positive results with our efforts to restart affected infrastructure.”Also read: Microsoft working on ‘alternate workstreams’ as outage fix fails to deliver expected resultsMatthew Haupt, a portfolio manager at Wilson Asset Management, said the firm’s small cap team told him that some trading volumes in equities have fallen on the back of the blackout.The outage has also left Kenneth Goh, who is travelling for work in Malaysia, unable to get market updates that help inform his advice to private clients, and it’s made worse during a volatile week of trading. “It has been super irritating,” said Goh, director of private wealth management at broker UOB Kay Hian, who is relying on patchy phone calls to speak with clients. “If the outage crosses 24 hours, then we’d be in the red zone.”