Summary of Issues: MDCrashReportTool, Backup, Sync, Preparing to Sync

Summary of Issues: MDCrashReportTool, Backup, Sync, Preparing to Sync


Disclaimer: This summarization is sourced from multiple community threads. By no means am I claiming this summary is all encompassing nor am I claiming to be a subject matter expert. Not everyone is having the same experience. Let's see how it goes anyway. Hopefully you will find it helpful.


What is the issue?

Data sync error details are collected and reported to Apple by an automated tool (MDCrashReportTool) which is known to sometimes stall, never giving control back to the parent process.

Is this a new issue?

No. MDCrashReportTool has been in existence since at least July, 2008 and the "stalling issue" has existed since 2009 and perhaps prior.


Is Apple actively working to resolve?

Only Apple can answer the question. Apple has acknowledged awareness of the issue but defects unresolved for so long are not likely to be resolved anytime soon, if at all.


Does this issue impact both Apple and Windows users?

Yes. Sync processing can be initiated via the Finder app for Apple users with current macOS software or from iTunes for Windows users and Apple users on older versions of macOS.


Are all users having this issue?

No. Devices synched using iCloud do not seem to be experiencing the issue. Users that sync data between devices initiated from the Finder or iTunes apps may experience the stalling issue.


Is this an Apple Watch issue?

No. Users both with and without an Apple Watch report experiencing a sync stalling issue so this is not exclusive to Apple Watch users.


Is this a cable issue?

No. Regardless of whether the device is wired or wirelessly connected, the sync process may fail/stall. One difference is a wire connected device that has failed to sync, if disconnected and reconnected while the "automatic sync when connected" setting is on will immediately attempt to continue where it last failed. With this setting turned off, and the setting for "show this iPhone when on WiFi" is set to "on", a sync will only begin if clicking the SYNC button and it will start fresh instead of where it last stalled. This will not guarantee a successful sync but does illustrate this is not a cable issue.


A stalled sync may complete after a force quit of MDCrashReportTool. How?

MAC computer: open the Activity Monitor found in the Applications/Utilities folder. In the app, search for MDCrashReportingTool. Highlight the process name and click the ⓧ icon. Select Force Quit from the popup menu.

Win computer: start the Task Manager. In Details, find NDCrashReportTool (may need to expand iTunes to see it). End NDCrashReportTool.


Is force quitting MDCrashReportTool a recent discovery?

No. Using this method has been around since release iOS 5. Also, there is a January, 2008 thread in the Apple Community (Title: Can't sync music) that mentions MDCrashReportTool.


Is force quitting MDCrashReportTool a fix or solution?

No. While this will allow the Sync to complete, no software is modified to correct the root cause. Until then, for every stall, a force quit is need to complete the sync.


Is there a way to automate the process so sync does not stall?

Yes. One way is to rename the MDCrashReportTool file extension so the process cannot be executed. Alternately, one might replace the file with a same named file that does nothing but return control to the parent process. Instructions are not included here as steps are dependent on the operating system and for iTunes users, whether the app is installed locally.


Is there a negative result in causing MDCrashReportTool to quit?

Yes/No. MDCrashReportTool automates error reporting. Prior to this tool development, the user would have to manually find, extract and publish error details to file a ticket with Apple. Quitting the tool puts error reporting responsibility on the user, likely resulting in fewer reports going to Apple.


Note: Running a "backup" is a five step process of which step 3 of 5 is "Preparing to Sync". A force quit of MDCrashReportTool will cause step 3 to complete in a flash but in testing, it appears steps 4 and 5 do not run. This leaves an open question of whether the resulting backup is complete. Apple may need to provide an answer.


What has not been addressed above:

(1) Effect of modifying settings for what is included in a sync

(2) How to identify file(s) the sync could not process, if any

(3) Does cancelling MDCrashReportTool leave behind log files that are never deleted?

(4) Instructions for renaming MDCrashReportTool

(5) For a stalled SYNC, any data not moved from iPhone to computer and/or computer to iPhone

(6) For BACKUP, the data result restoring an iPhone from a backup that previously stalled


-R.

Posted on Dec 20, 2023 12:56 PM

Reply
Question marked as Top-ranking reply

Posted on Dec 31, 2023 8:32 AM

TerPri wrote:

I am able to navigateto MDCrashReportTool but am unable to rename it. Can anyone provide directions on how to accomplish this?
thanks

TerPri, if you are trying to rename the tool via the Activity Monitor, that is definitely not the way to do so.


You will need to navigate to the file using Finder (assuming you are on a Mac) as follows:


/Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/AppleMobileDeviceHelper.app


Right click on AppleMobileDeviceHelper.app and select "Show Package Contents" followed by /Contents/Resources/MDCrashReportTool


From there you should be able to rename the tool if you are signed into your computer with admin rights.


Good luck

-R.

Similar questions

82 replies

Jan 10, 2024 1:59 PM in response to Ron_NJ

bwadma wrote:

In reply to Northern-Survivor
I face the "hanging sync iPhone to Mac" as well (iMac24-M1 14.2.1, iPhone-13mini 17.2.1), since the update to 14.2/17.2 - not before that update. System version 14.1.x / 17.1.x did sync OK for me.
• I always use the "old" USB cable connection, and I have "Automatically sync when this iPhone is connected" activated in the "iTunes" Finder window
• Yes, I do have (also) an AppleWatch (Watch-9 10.2)
• As reported e.g. at reddit, I had several times (but not always) success with activating Flight Mode on the AppleWatch when a sync was hanging at "Step 2 preparing to sync".

Do you mean you wait for the sync to hang and then turn Watch to Flight Mode?


Before attempting a sync I've tried:

/ power off the Watch

/ switch to Watch to Flight Mode (which also sets iPhone to Flight Mode)

/ unpairing the Watch

None of that makes any difference in my case.


As you say sometimes the sync is successful, but not always.

I can't find any reliable and repeatable workaround that doesn't involve a Force Quit or rename (or relocate) of the crash report tool.

Syncing over USB and disconnecting/reconnecting the cable remains my favoured option. It mostly works.

Feb 2, 2024 2:33 PM in response to hitlength

hitlength wrote:
They want you paying a subscription for Apple Music and for larger iCloud storage.

An alternative is iCloud Music Library. That requires an iTunes Match subscription, but iCloud Music Library is free and doesn’t count against your iCloud storage. You can stream or download songs from the Library to your Mac or iOS device ( it doesn’t use syncing ) . And iTunes Match is not as expensive as Apple Music.


Another alternative is to manage your music manually (check the box in the Finder , which turns off syncing) .

Dec 26, 2023 8:32 AM in response to Adam@1955

Adam@1955 wrote:

hi @Ron_NJ
I used a backup created with a process that was stopped by force quitting the MDCrashReportTool to reset my iPhone. The result was that even the newly set up iPhone could not be synchronized.
I then restored the iPhone with an old backup from the time before IOS 14.2 and I had no problems synchronizing the iPhone. But after 2-3 synchronizations the problem was there again. I can't explain why exactly.

Hi Adam, it sounds like the restore done with the old backup put your phone in a state where there were no sync errors between devices and therefore, MDCrashReportTool did not need to run. But then you make reference to "after 2-3 synchronizations the problem was there again" which makes me wonder how much time passed before the issue reappeared. Assuming the 2 or 3 sync processes were not run one right after the other, over time your devices needed to be brought back into sync. It is then the process detected an error and the issue with the MDCrashReportTool stalling returned. It seems to make sense... just not a happy result.


-R.

Dec 26, 2023 9:36 AM in response to Adam@1955

My user ID on my mac is an Admin. If you are not an Admin you may not be able to rename Mac standard software.


If your Mac belongs to your company or is under administrative control by your company you may not be able to rename Mac standard software.


If the MDCrashReportTool is running you might not be able to affect the software on disk because it is in use. You would need to kill it, and ensure you do not start another sync so it does not get restarted, before trying to rename the program.


Note that the path to the tool starts at /Library (the Mac's Library) , not ~/Library (your account's Library).


The tool is actually embedded in an application tree, not the regular file system tree. The permissions in such a tree may be different from the permissions in the file system tree; I'm not sure how they work. The controlling permissions may actually be on AppleMobileDeviceHelper.app.


There are other system permission mechanisms that have prevented me from changing Mac software in the past, so I was rather surprised my user WAS able to change it.


Jan 26, 2024 10:56 PM in response to Ron_NJ

I'm going to apologize upfront if what I'm about to write here doesn't fit into this category.

So for over a month now, ever since update to iOS 17.2, my phone (14 Pro Max) hasn't been able to properly sync with iTunes. For the time being I've been going into task manager (Windows 10 Pro PC) and ending the MDCrashReportTool process. That works. At least I'm able to add and remove music as I wish.

With that in mind I've now updated (January 26, 2024) to iOS 17.3 and the "passes" (concert tickets) from Ticketmaster are all disabled. Apple says it's a known issue and that they're working on it. That's what they said about the sync problem and that's still going on. I have a feeling they say that about everything.

The question I have then is, does one issue have to do with the other? Is the reason my tickets are disabled that my phone won't sync without force quitting the MDCrashReportTool? Anyone else experiencing this problem?

Apple support is of no help in this matter. All they could suggest was transferring my tickets to someone I trust with a Ticketmaster account, have them transferred back, re-add them to Apple Wallet. That didn't work.

If anyone has any suggestions on a fix, I'm all ears.

Thank you in advance to anyone who reaches out to help.

Jan 26, 2024 11:49 PM in response to spawnster

I think your observations do fit.


I suspect we’re seeing the infinite data set problem. That is, we have standard software - the operating systems and applications; yes they’re customisable to some extent by “settings”, but we’re all using the same software for any given version.

But we all use it differently, on different hardware, each users data (emails, music, photos, files etc, etc ) is unique to them. And there are millions of us. It’s an infinite data set. And it’s not a stable beast, every update of the OS and apps brings new features which we hope won’t disrupt existing features.

So how does Apple make sure everything still works as it should every time they make a change - and still works for all users. The answer is they can’t.

Sometimes glitches in the software show up in different ways , dependant on the data.

You have a problem with passes, I don’t, but I do have a rogue video file that is not in my Mac music library but it shows up in the music sync to my phone. Unique users with unique data, unique problems, individual workarounds, or no workarounds at all in some cases. If we’re lucky a workaround will work for multiple users.


It not surprising that Apple Support looks weak, they can only give generic advice, such as reboot your machine in Safe Mode, or reinstall stuff. It’s not tailored to your unique environment.

Occasionally Apple will identify a problem and fix it.


I empathise, I’ve spent hours playing with this issue , which ultimately led me to a solution (don’t sync that troublesome playlist), that works for me, and only me.


And my nearest Genius Bar is over 1000 miles away.

So sorry I can’t help. N-S

Dec 25, 2023 11:11 AM in response to Ron_NJ

I use USB syncing for calendars (instead of using iCloud); all media are managed manually.


Since updating to Sonoma 14.2.x and iOS 17.2.x, the symptoms described above happen on my Mac.


A difference, however, is that after force-quitting MDCrashReportTool, the syncing proceeded until an alert displayed that said "Syncing with iPhone will change more than 25% of your calendars, events, or to dos on

this computer." In the alert, over 6,000 events were in the alert's Delete column.


Not wanting to risk losing calendar events on my Mac, I clicked the Sync later button. The sync failed…no relevant events on the iPhone.

Dec 25, 2023 12:21 PM in response to Barry F-H

Barry F-H wrote:

after force-quitting MDCrashReportTool, the syncing proceeded until an alert displayed that said "Syncing with iPhone will change more than 25% of your calendars, events, or to dos on
this computer." In the alert, over 6,000 events were in the alert's Delete column.

Wow, that's one I have not heard of before your post. It sounds like one of your devices (I am guessing your Mac) has dropped the 6,000 events and the sync wants to remove them from your other device (iPhone). Compare the device calendar app and your computer calendar app. Which one would you say is more current?


-R.

Dec 26, 2023 9:02 AM in response to Adam@1955

Adam@1955 wrote:

Hi @ rsworden

unfortunately I can[not] rename the MDCashReportTool. I do not have access rights.
I would be very interested to know how you renamed the app.

Adam, while you are waiting for rsworden to reply, I will offer the following:


If you have admin rights and the tool is not currently running, I would expect that you can rename the app in Finder. Alternately, using a batch file run inside the terminal app should also do what you want.


Sorry but I will not be advising how to do so since I stopped writing batch files when I left the Windows space ten years ago and have never written any for macOS processing.


Finally, I found another temporary solution to the stalling issue that does not require the renaming or cancelling of the MDCrashReportTool. It was offered by karstene69 in the thread Stuck in “Preparing To Sync" - Apple Community

(page #10 with timestamp Dec 26, 2023 9:41 AM). Take a look.


-R.


Dec 30, 2023 4:05 PM in response to Northern-Survivor

Northern-Survivor wrote:

A bit more on the Watch connection., Ron.

Your experience differs from others I’ve read . Some users say unpairing their Watch does make a difference to the sync. I assume from the posts I’ve read that a phone that’s never been paired to any Watch doesn’t see this bug in the sync. It could be that it is a log and analytics data issue and it takes time for all the logs to be removed (as per Apple Support) . IOW, unpairing a phone does not return the iPhone to the same condition it was in before pairing ……. that takes time.
Still hoping for someone to prove me wrong and the Watch and/or its log data are red herrings.
All in all not much progress, but we are trying to debug Apple’s software with both hands tied behind our backs - and blindfolded.

N-S, As you stated, having a watch paired with an iPhone and later disconnecting it does not put the iPhone in the same state as before the watch was first paired. I've since come around to that point.


Thanks for staying invested in this issue.

-R.

Dec 31, 2023 9:39 AM in response to TerPri

Hi again

I can not even create a folder in that same location. I can of course move the file onto my desktop but that just creates a copy. I guess there must be some way for me to get a root user account or to use terminal to allow me to access this folder.

Hammer may be the only option.

The only way I can sync my new iphone15 pro is to force quit the MDCrashReportTool. Easy enough to do but really ... Without this discussion I would be sunk.

Thanks


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Summary of Issues: MDCrashReportTool, Backup, Sync, Preparing to Sync

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