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

Great note! Coincidentally I encountered this yesterday and have been trying to solve it.

Regarding disabling MDCrashReportTool: The path to it is

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

Note that to navigate all the way to the bottom we need to use "Show Package Contents" on AppleMobileDeviceHelper.app.

I renamed MDCrashReportTool with no trouble. I expected to get "insufficient access" but did not. After renaming the tool, I can sync my iPhone completely: steps 1 through 4 start and end normally.

I am on Sonoma 14.2 and iOS 17.2.

Your mileage may vary. Not responsible for anyone's issues if they choose to rename an Apple tool.

Thank you for your research!

When you say you cannot rename the tool, do you mean (1) you do not know how, or (2) you know how but you get an error message or are otherwise blocked?

(1) Using Finder, navigate via the folder structure until you see MDCrashReportTool. Right-click on it and you should see a drop-down menu that includes Rename. Choose that, then add text to the end of the file name. Do you get an error message at this point?

No, you probably cannot create a folder in this location. No, you probably cannot move the tool from the Resources folder. From the point of AppleMobileDeviceHelper.app on down, you are navigating folders within an application package, not "really" folders within the file system. Finder can navigate it, but the .app was built by Xcode, and Finder's abilities are limited there. Renaming is one of the few things you can do with Finder.

(2) Using System Settings > Users & Groups , do you see Admin under your name?

If not (you are not Admin), you will need to either promote your User to be an Admin, or log in as an Admin user to do the rename.

If so (you are Admin) there is something else going on with your Mac (see my earlier comment), e.g. your Mac might be locked down by a company administrator.

• It might be possible for you to rename the tool if your Mac has been freshly booted and your iPhone is turned off, so the tool has not been referenced by the sync process.
• If that doesn't work, it might be possible to rename it if you boot your Mac into single-user mode so you have more access and fewer system processes are active.
• If that doesn't work, you might have to disable System Integrity Protection to accomplish the rename. If you are comfortable with that, instructions are available elsewhere on Apple's site.

Thank you very much, renaming MDCrashReportTool to something random fixed the issue. But it requireds disabling disabling Syetm Integrity Protection to make this system modification. Maybe the OP would be best to add this fact in his post as most people have SIP enabled by default so will find issues renaming the file.

Ron_NJ wrote:

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.

Just wanted to add here, if you cannot rename MDCrashReportTool because of permissions being denied (or the option isn't available when you right click) you could try disabling SIP.

Disabling SIP is very dangerous, and I cannot emphasize enough that you need to know what you are doing before you do.

Here is a guide to disable it: Disabling and Enabling System Integrity Protection | Apple Developer Documentation

In brief -

1. Boot into recovery (on M1/M2 chips just shut down and then hold down the power button while it is booting back up)
2. Options > Utilities > Terminal
3. Run "csrutil disable"
4. Restart and go rename MDCrashReportTool
5. Boot into recovery
6. Go back into Terminal
7. Run "csrutil enable" (if that throws an error run "csrutil clear" instead)
8. Run "csrutil status" and make sure SIP is enabled!
9. Restart

Hope this helps!

A good analysis of a quirky problem that doesn’t affect users in the same way. Very helpful.

Hat off! Ron, thanks

After several days of trying various things and checking the latest posts to various threads , here’s where I’m up to.

In the Finder, boxes “show … on Wi-Fi” and “automatically sync… when connected” are both checked

1. Syncing over wi-fi always hangs.
2. The phone occasionally disappears from the Finder sidebar.
3. Syncing over a wired connection sometimes works first time and sometimes hangs. When the sync hangs disconnecting and reconnecting the USB cable causes the backup and sync to complete and produces a valid backup. So it’s important not to skip the backup. This is now my favoured workaround.
4. Looking at various posts in other threads I’m left wondering if anyone who doesn’t have an Apple Watch has this problem. The sync always works fine on the iPad. So what’s different about the iPhone? Could it be that Watch diagnostics data causes a problem in the iPhone backup/sync which invokes the crash reporter which hangs? Just my WAG.

Thanks for all your efforts Ron, it’s much appreciated .

On the iPhone go to Settings > Privacy & Security > Analytics & Improvements. Uncheck "Share iPhone & Watch analytics.

This caused my iPhone to sync properly - just after I wrote that long update!

I found this here: https://discussions.apple.com/thread/6743151?sortBy=best

Try manual media management. That doesn’t rely on Sync processes.

In the Finder check “Manually manage music,……”. Then, in the Music app, drag and drop selected songs onto your iPhone. Works quite well if you want your entire music library on your iPhone. It’s a bit cumbersome is you manage content by playlists, but it is an alternative to Force Quiting the crash report tool or renaming/moving it.

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". The iPhone did disappear from the Finder window sidebar for a short time, then re-appeared and the sync continued.
• It is mostly Photos that need to sync in my case (the AppleMusic abo works without sync on several devices). Syncing Photos from Photos.app completes with success after Force Quit of MDCrashReportTool.

It would be great if all people who read this thread because they are affected would submit a report at

Feedback - iPhone - Apple

and/or

Product Feedback - Apple => your Mac.

All the best for 2024!

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

I have tried point 6.

Unfortunately, the error is included in the backup, so that no usable backup is obtained.

Regards Adam