Outlook 2016 - Attachment drop down rapidly closes - Microsoft Community

we have several users attachment drop down in outlook briefly show disappear.

it shows 1 or 2 seconds.

there few other threads on here various workarounds, looking permanent solution, thought share i've discovered see if has ideas on can try next.

workarounds , results:

• delete generic credentials in control panel
  • this works, not solution 2 reasons:
    • a. not of users comfortable doing this, , hundreds of users impractical.
    • b. works temporarily. after few weeks started having same users call same issue.
• remove , re-add mail profile in control panel (or recreate user profile)
  • see issues above.

• switch email html plain text
  • non-issue in case, not same issue. issue resolved in update.
• reinstall windows
  • might work, makes no sense in production environment
• repair office installation
  • i'm convinced these responses done kind of bot. repairing office not fix problem, , needs stop being suggested. 
• sign out of office 365 , sign in
  • we not using office 365 , if were, suspect resolve issue short period of time above workarounds.
• tap "b" on keyboard right after opening drop down
  • this helps, doesn't solve issue. opens browse window because b shortcut key if @ browse option in attachment drop down.
    • user must hit b @ right time work
    • doesn't show recent files, usual browse window
    • does not resolve issue
• add attach quick access toolbar in outlook
  • this works, sort of.
    • there 2 attaches can add. 1 arrow (shows recent items when clicked) not work when user affected issue. other usual browse window appears above. 1 work, points issue recent items drop down , not actual attachment function. so, not solution.

my theories:

***edited remove theories proved inaccurate***

1. will update briefly, more testing done.

addt. info:

• office 2016 (not using 365)
• windows 10
• latest updates outlook , windows installed
• does not happen users
• does not matter format email in (html/plain text/etc)
• cannot reproduce on test machines, can't find similarities between users
• does not happen if log computer main pc, because new profile created.

i still testing , collecting data users when happens, have not been able come permanent solution.

if has ideas or suggestions, willing try. workarounds posted above some.

moved from: office / outlook / windows 10

hello,

some of possible reason why you're having performance issues due corrupted system files or software. suggest repair outlook 2016. click link learn how repair office application , follow on-screen instructions.

let know happens after.

Office / Outlook / Windows 10 / Office 2016