Hi Andrew,
I read that you solved the soagent issue, but now you are fighting against the mac mail client issue... good luck with it, but just to let you (and everybody else who is reading this post) know it, since I had installed 10.11.2 I experienced a lot of problem working with my MBA. Only during last week, I finally have been able to solve those problems. Now I feel more comfortable with my MAC, but I have been really thinking about moving to something different (linux or evenly windows 😝) because I wasn't able to work without experiencing those issues during my job. So often I needed to stop because I was hearing noise from my CPU fan, looking at the activity monitor icon and noticing that there was an intensive usage of my CPU due to the processes soagent and also another one named callsericesd (maybe is not your case) that was causing two of the four available I5 cores were used at 100%. And the only way to get rid about of that was to force stop both processes. I also opened a couple of SR with Apple (after installing 10.11.2) and they remotely connected with me, but at the end they haven't been able to solve my issue. So, day by day, this has been decreasing my confidence in Apple products, and it also represented something bad for my professional reputation 😠 ... I mean, it was a shame seeing myself imprecating against my laptop... killing processes... rebooting... rebooting, yes! something normally i did not more than a couple of time every month and above ten time every day after 10.11.2, what a mess!
So, about soagent and callservicesd, finally I solved doing what has been suggested here Re: Problems with callservicesd and soagent thanks to alecthomas.
What I did it was:
- I opened system preferences and deleted all the internet accounts I had 😐
when you do it, you lose all your messages from your mac mail app, so save them to a local folder you can create in mail before to proceed with the account deletion. Same thing if you are syncing your contacts: export/save all your contacts before proceed, otherwise you might lose them.
- rebooted my MacBook Air (something I learned well during the last month)
- after the reboot, I recreated all my internet accounts
I also found someone who said to go in (home)/Library/Preferences/... and delete some xxx.plist files there, but I didn't need to touch anything there.
After I recreated my internet account to sync my personal gmail account, the first sync with google needed to download thousands of emails from there, so I think is more than expected that it will consume time, band (internet connection) and CPU resources, but now all the problems with soagent and callservicesd has gone and I'm happy again with my MBA.
About you current problem with the OSX Mail app, I solved other problems I started experiencing after updating to 10.11.2, by disabling the SIP protection which has been introduced by 10.11.2. I don't know, but you may try it. If you don't solve the problem you can re-enable SIP protection on OSX. Currently I disabled SIP and I'm waiting for 10.11.3 to see if I can enable it without problems, but I will wait at least one month before applying any new update to my MBA monitoring the community to see if there are any new issues with them.
Hoping to help everyone who suffered like me after 10.11.2 😉