Office 365 Slow, unresponsive and takes 5-10 min to load Shared Calendars

Posted on 2014-08-29
Last Modified: 2014-09-09
Windows 7 Pro 64x. Office 365, Outlook loads slow, calendar takes forever to show shared calendars. Has responsibility for 7 user shared calendars. Running without error since February. Ran both Quick and Online repair. Backed up .ost to .pst, deleted profile and made new profile. I can uninstall and re-install the program, don't want to waste the time if its the equivalent of running the Online Repair. Should I re-install?
Question by:drmll
    LVL 37

    Expert Comment

    by:Vasil Michev (MVP)
    7 shared ones is a bit too much. Not only it will consume more resources and bandwidth, the .ost file will explode as well. I strongly advise you to configure them in Online mode and/or add them only when needed. Opening shared calendars will also contribute to the slowness, as they are cached by default. What is the size of the local .ost file?

    Don't forget about OWA as well, if it's just a simple one-time task, no need to add shared mailbox/calendar to the Outlook profile, use OWA instead.

    Accepted Solution

    Solution; Disable "Download shared folders" in advanced settings under users mailbox settings.

    Author Closing Comment

    That's what fixed it.

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