Outlook for Mac 2011 (14.3.9) on Mac OS X Mountain Lion (10.8.5) and Snow Leopard (10.6.8) has stopped communicating with our company Exchange server. Last week, Wednesday February 19th, 2014 my iMac with OS X Mountain Lion 10.8.5 received an error on Outlook for Mac 2011 14.3.9 that 'Mail could not be received at this time. The server for account 'xxx' returned the error 'Logon failure: unknown user name or bad password.' Your username/password or security settings may be incorrect. Would you like to try re-entering your password?'

I have two Exchange accounts in my mail client and received this error for both profiles. I tried reentering the passwords and still could not get it to work.

I know it's not an issue with my Exchange network credentials because mail on my iPhone and iPad never lost service. Also, on that same day, mail continued to work in Outlook for Mac 2011 14.3.9 on my MacBook running Snow Leopard 10.6.8. Occasionally I could reboot my system, relaunch the application, and new Exchange emails would load but then would immediately time out and give the same error again. I also would from time to time, check or uncheck the 'SSL' setting in the Advanced Account settings and could get connectivity for about 1 hour until it would time out again. Then, Thursday, February 20th, 2014 Outlook for Mac 14.3.9 gave the exact same errors on my Macbook running Snow Leopard 10.6.8. Now I cannot manage my mail on either computer and must do it all on my iPhone or iPad which are still working just fine.

The Mac operating system that it supports are versions macOS Sierra 10.12, 10.11, 10.9, 10.7 and all the lower releases. This signifies that the software supports the latest Mac OS and Outlook for Mac versions in addition to the earlier editions.

Both OS's and Office products are fully up-to-date with the latest softwares and no changes were made from our IT department to the Exchange server. Myself and my IT department are stumped at this point and cannot seem to find a viable solution out on the net.

Any assistance or suggestions is GREATLY appreciated! I have exactly the same problem - i can log onto exchange and receive emails through my home network on my nokia 920, my iphone 4, my ipad 2 but on the 18th Feb all access to mail via office stopped on my macbook pro. My version of office is 14.1.9 and osx 10.8.5. Coincidently, some time shortly after that date my work laptop (windows 7) stopped receiving mail over my home network or wifi dongle and the only way i could receive mail is to have direct connection with my office network via lan or office wifi. Macbook still a problem but phones and ipad still able to access.

I have tried changing passwords and saving to keychain, deleting keychain passwords, setting up fresh mail accounts but nothing seems to work. If someone could point me in the right direction that would be greatfully received as my IT department is also stumped. Eric and ckh333, thanks for the clarification. FYI I tried deleting the password in Keychain but still no luck, because when I open outlook and it now prompts me for the password, I still receive the same password error even though the password works with my other devices! In a bid to start afresh, I've now deleted the Outlook account and will re-establish it once I've confirmed the settings from the Exchange provider.

Will keep you all posted if this works. In the meantime if there are any other suggestions it would be appreciated! Apple Footer • This site contains user submitted content, comments and opinions and is for informational purposes only. Apple may provide or recommend responses as a possible solution based on the information provided; every potential issue may involve several factors not detailed in the conversations captured in an electronic forum and Apple can therefore provide no guarantee as to the efficacy of any proposed solutions on the community forums. Apple disclaims any and all liability for the acts, omissions and conduct of any third parties in connection with or related to your use of the site. All postings and use of the content on this site are subject to the.