thanks for encouraging me to look at the driver! i found/fixed the problem:
i looked at system.log using the console app. and i found lots of these:
Aug 1 23:42:29 Sacred com.apple.xpc.launchd[1] (com.Iris): Service only ran for 0 seconds. Pushing respawn out by 10 seconds.
Aug 1 23:42:39 Sacred com.apple.xpc.launchd[1] (com.Iris[11189]): Service could not initialize: Unable to set current working directory. error = 2: No such file or directory, path = /Library/Easel/iris: 16G29: xpcproxy + 11215 [1386][1E2A2740-D4E5-342E-A502-4792BD02598D]: 0x2
Aug 1 23:42:39 Sacred com.apple.xpc.launchd[1] (com.Iris): Service only ran for 0 seconds. Pushing respawn out by 10 seconds.
Aug 1 23:42:49 Sacred com.apple.xpc.launchd[1] (com.Iris[11191]): Service could not initialize: Unable to set current working directory. error = 2: No such file or directory, path = /Library/Easel/iris: 16G29: xpcproxy + 11215 [1386][1E2A2740-D4E5-342E-A502-4792BD02598D]: 0x2
i checked /Library/Easel/iris and it does not exist! but /Library/Easel/Iris does (capital “I”). someone made a typo somewhere…
Sacred:~ frank$ cd /Library/Easel/iris
-bash: cd: /Library/Easel/iris: No such file or directory
Sacred:~ frank$ cd /Library/Easel
Sacred:Easel frank$ ls
Iris
my fix was making a symbolic link from Iris to iris:
Sacred:Easel frank$ sudo ln -s Iris iris
Password:
Sacred:Easel frank$ ls -al
total 8
drwxr-xr-x 3 root wheel 136 Aug 1 23:44 .
drwxr-xr-x+ 57 root wheel 1972 Aug 1 00:15 …
drwxrwxr-x 9 root admin 510 Aug 1 23:44 Iris
lrwxr-xr-x 1 root wheel 4 Aug 1 23:44 iris -> Iris
Sacred:Easel frank$
and all works now!
btw: on a mac, i think/remember, you can format your disk either as case sensitive or insensitive. so case insensitive formatted drives will not have this problem