My overseer stopped working exactly one (use of overseer) cycle after the last patch. I have plenty of agents. They are available. They have the required skills. But I can't start any missions. When I click on the "select agent" button, the available agents do not get displayed, and the icon just above the select agent button is highlighted, this has gone on for days, through camp/relogin cycles, through computer reboots. I submitted a bug report in game after instructed to do so in response to a petition. I was told it was "sent to the devs" but have heard nothing since then.
Doesn't necessarily help you, but I've used Overseer multiple times across multiple accounts without a single issue (other than the disappearing quest thing). Do you have only one account with a 85+ toon?
Something to try though it may not fix your problem: Win10 Instructions: Right click on your windows clock (bottom right of taskbar) Select "Adjust Date/Time" Scroll down & click on "Add clocks for different time zones" Then on the new pop up window select the top right tab "Internet Time" Click on "Change Settings" Click on the drop down menu so all of the text is highlighted, press backspace to clear & type in pool.ntp.org & then click "Update Now" Then ok on the boxes to close. Your PC Clock should now sync with the best internet time resource. This will at least eliminate any time synchronisation issues between your EQ Client & the EQ Servers which I know can cause some issues with Overseer.
It would be good to know. Having the same issue. Had to reduce resolution, now can't get to bottom of overseer window to resize. scroller on side of overseer below screen. I've tried all the suggestions above, nada. even deleted my default ui in hopes it would fix, nope.
I fixed it. Here's how. Go into your UI_[insert character name here]_[server].ini file; search for overseer. delete everything in the overseer section of the text file. save file. log back in. Hooray!