Two mdm errors and how to resolve them

First one is kind of shaky, the second one is definite.  I will update this post and make note of it if my information changes.  Last month I was receiving “the configuration for your iPad could not be downloaded from [my client’s server] NSURLErrorDomain -999.”  I found all kinds of solutions online relating to management suites, but I’m not even going to mention them because they were irrelevant to the solution in my case.  The only difference in my setup between functioning and non-functioning was the devices I was deploying started coming with iOS 11 instead of iOS 10.

This particular setup is just preparing the devices with Configurator 2, no DEP, then going through the iOS initial configuration of which the major steps are joining the wifi network, accepting enrollment, and logging in with the user’s account.  On initial setup of this system around the middle of 2017 I was receiving errors about SCEP enrollment, which was not being used.  That was fixed by enabling all the setup steps instead of trying to customize them.  (Also, see “4/17/18 note,” below.)

The change I made which fixed this problem was editing the enrollment url from:





This month on trying to deploy another device I started receiving a new error, “the configuration for your iPad could not be downloaded from [my client’s server] “Invalid Profile.” To fix this open Configurator 2 -> Preferences -> Servers -> + -> [enter a name like mdm Jan 2018] -> [for “host name or url” use only the fqdn and no path info so it autodiscovers the full path, i.e. https://fqdn/]. This will fetch the most current cert/info via built-in autoconfig.

After receiving the “Invalid Profile” message I needed to manually erase the device to begin again, but after erasing and re-preparing it the steps went back to working perfectly.

1/25/18 note: My employee was testing this, it failed even with a newly autodiscovered server entry.  However prior to use instead of being brand new (in my case) he used Configurator 2 to erase it.  Using the built-in “Erase All Content and Settings” did allow the process to proceed.  Next new iPad I get I’ll try erasing it prior to preparing it using Configurator 2 and leaving the existing server entry in place.  If that works I’ll update this post.

4/17/18 note: SCEP errors can also occur if port 80 is not open to the profile manager server.

If I’ve made an error or helped you out, I’d love to hear about it. Please email me at mdm@ this domain name (without the www.) Thanks!

The Lion City II – Majulah

I’m completely taken by this song.  It is not often I listen to the same song twice, nevermind on repeat on my car, phone, and home system.

The video?  Oh, it’s pretty.  Mindblowing too, if you try to figure out how you get a perfectly smooth time lapse over a period of months (years in some cases) where the source camera is clearly moving.

These artists are masters of their crafts.

Inside look at Trump – Art of the Deal ghostwriter “tells all”

Better settle down for a minute, The New Yorker is not one for brevity.  This is an intriguing story where I feel like I finally have a glimpse at the man behind the facade.

Keep in mind I’m not a black and white thinker; posting a story revealing an unflattering side of a major political candidate does not automatically make me a member of the other side.  I believe in nothing but a careful examination of facts, history, and general attention to detail.  Back to the article, one quick quote:

“An accompanying cover portrait depicted Trump as unshaven, unpleasant-looking, and shiny with sweat. Yet, to Schwartz’s amazement, Trump loved the article. He hung the cover on a wall of his office, and sent a fan note to Schwartz, on his gold-embossed personal stationery. ‘Everybody seems to have read it,’ Trump enthused in the note, which Schwartz has kept.”

Fascinating – “denying death its sting”

I helped eight people end their lives. By the time you read this, I’ll have ended mine

I realize this is a controversial topic but it’s hard to argue with this kind of sentiment: “The poet Susan Musgrave, who knew Al well, wrote of his final months: ‘Al looked at death the same way he has always looked at life—right between the eyes.'”

I’ve saved this for about half a year to share, I think it’s too good of a story not to.

Deleting Time Machine .inProgress backups

[Disclaimer: there are some very powerful commands mentioned casually here.  BE CAREFUL, I assume no liability for you recursively deleting or removing all permissions from your data.  Or for that matter, anything else as a result of a lack of caution or expertise!]

This was an interesting one.  Had a machine that kept having issues during Time Machine (TM) backups.  It completed the first backup successfully and then stalled on one of the next few backups.  In this particular case it’s multiple terabytes over a fairly slow connection so the first backup takes days.

Then it sits “preparing” for as long as you’d care to watch it.  First time this happened I monitored TM activity using and a backupd search string, nothing was really happening.  So then I stopped TM and tried to cleanup the .inProgress folder so TM could start over.  I was trying to force its recovery after (not completely covered) basic methods didn’t work.

This .inProgress folder completely refused to be deleted.  Nothing worked: started with rm -R and when it complained thought it was the usual system immutable flag.  That the file was locked.  Tried chflags -R nouchg and had no luck.  Tried some advanced variations of that, still nothing.

(Side note: this is my second round with this exact issue, the first time through I made sure the data was backed up elsewhere and formatted the drive, just for the sake of time efficiency.  Since the issue is back I have to address it head on.)

“ls -lahe” revealed files with ACLs set to deny access to everyone.  So I used chmod -RN to recursively remove all permissions.  I kept getting “chmod: Failed to clear ACL on file” and “Operation not permitted” despite being root.

So.  Hmmm.  I can’t remove ACLs prohibiting deletion on files which also have system immutable flags set, meaning I can’t change ACLs via any method.  I should mention that yes, I did check directory structure integrity way earlier in the process.  Taking a step back I realized this was a TM-created issue, so maybe tmutil can come to the rescue again.

Sure enough: Use tmutil listbackups just for verifications and then use tmutil delete snapshot_path [use actual path here sans brackets, e.g. /Volumes/ExternalBackup6TB/Backups.backupdb/ComputerName/2016-09-12-000400.inProgress/]

This returned the error “snapshot_path: No such file or directory (error 2)” AND YET in a separate session escalated appropriately “fs_usage | grep tmutil” showed the truth, that tmutil was furiously cleaning up all those untouchable files.  I later verified that the .inProgress folder had actually been removed.

Problem solved!  Hope this helps someone.  I love to hear when it does (tmutil@ this domain name) but if you’re too busy, no worries!

Tabs March 2016

Well the time has come to clean up tabs.  If I bookmark them I’ll never see them again, so I might as well share them.
So again I looked at microdata from the American Time Use Survey from 2014, which asked thousands of people what they did during a 24-hour period. I used the data to simulate a single day for 1,000 Americans representative of the population — to the minute.

More specifically, I tabulated transition probabilities for one activity to the other, such as from work to traveling, for every minute of the day. That provided 1,440 transition matrices, which let me model a day as a time-varying Markov chain. The simulations below come from this model, and it’s kind of mesmerizing.


Take a second look at these.  Amazing.

Rob Gonsalves

Man quits job after visiting Burning Man, spends 10 yea


Sure, skip around especially the intro, but if you’re into speed these boats are something else.  Never seen it from this perspective before!


Full of interesting tidbits:

Love this story, especially details like the black gloves.

Milky Way tracking.

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Does this…. work?

I dunno about best in the world, but this kitchen does have some pretty killer features that aren’t obvious at first:

7 Reasons Why This Kitchen Was Named Best In The World

Reddit title was “Smearing time like butter.” Not even going to try to improve that.  Takes a little while to get really into it.


A place for random thoughts.