Make sure that your security software is set up correctly. Set up steps vary by software, so contact the developer for specifics.
Applications signed by Apple automatically receive incoming connections on OS X. This article doesn't apply if you're using the macOS built-in Application Firewall.
Server connections
The following servers are used by macOS, iOS, and iTunes:
| Apple servers | Other servers |
|---|---|
| albert.apple.com | evintl-ocsp.verisign.com |
| deimos3.apple.com | evsecure-ocsp.verisign.com |
| gg*.apple.com | *.amazonaws.com |
| gs.apple.com | *.symcb.com |
| itunes.apple.com | *.symcd.com |
| *.itunes.apple.com | *.digicert.com |
| mesu.apple.com | |
| skl.apple.com | |
| *.mzstatic.com | |
| *.cdn-apple.com | |
| appldnld.apple.com |
Common ports
The following ports are used or relied on by Apple software, macOS, iOS and iTunes:
| Ports | TCP or UDP | Used by |
|---|---|---|
| 80 | TCP | World Wide Web and services, iCloud, QuickTime Installer, iTunes Store and Radio, AirPlay |
| 443 | TCP | TLS websites and services, iTunes Store, iCloud authentication and DAV services |
| 1231 | TCP/UDP | Network Time Protocol (NTP)* used for network time server synchronization, AppleTV Network Time Server Sync |
| 554 | TCP/UDP | Streaming media players, AirPlay |
| 1900 | TCP | Bonjour Service |
| 3689 | TCP | DAAP, iTunes Music Sharing, AirPlay |
| 52231 | TCP | iCloud DAV Services (Contact, Calendars , and Bookmarks), Photo Stream |
| 5350 (UDP) | UDP | Bonjour Service |
| 5351 (UDP) | UDP | Bonjour Service |
| 5353 (UDP) | UDP | Bonjour, AirPlay, and Home Sharing Services |
| 8000-8999 | Web service, Internet Radio streams | |
| 42000-42999 | Internet Radio streams |
Learn more about TCP and UDP ports used by Apple software products. Blocked ports are often related to errors numbered in the 3000 range.
iTunes for Windows processes
iTunes for Windows installs some processes that run in the background. Learn more about what each process does.
| Process | What it does |
|---|---|
| AppleMobileBackup.exe | Backs up the data on your iPhone or iPod touch |
| AppleMobileDeviceHelper.exe | Listens for commands to help iTunes communicate with devices |
| AppleMobileDeviceService.exe | Allows iTunes to recognize iPhone and iPod touch |
| AppleMobileSync.exe | Synchronizes iPhone or iPod touch data with your computer |
| distnoted.exe | Allows iTunes to sync with iPhone and iPod touch |
| iPodService.exe | Allows iTunes to access devices |
| iTunesHelper.exe | "Listens" for commands to help iTunes communicate with devices (such as iPod) |
| iTunesPhotoProcessor.exe | Transcodes photos and artwork for devices |
| MDCrashReportTool.exe | Extracts log reports from the device and submits them to Apple (if selected) |
| mDNSResponder.exe | This lets iTunes discover services on the local network (music sharing, Apple TV, AirTunes). It's also known as Bonjour for Windows. |
| SyncServer.exe | Coordinates the synchronization processes |
| qttask.exe | This provides a QuickTime icon in the Notification area (system tray) of the Windows Task bar. This process might or might not appear, depending on your QuickTime setup and if the QuickTime icon is enabled in the Notification area. |
| Processes depending upon Sync configuration | What it does |
| dotmacsyncclient.exe2 | Syncs the device with iCloud |
| com.google.ContactSync.exe2 | Google contact syncing |
| com.apple.IE.client.exe | Syncs the device with Internet Explorer |
| com.apple.Outlook.client.exe | Syncs the device with Outlook |
| com.apple.Safari.client.exe | Syncs the device with Safari |
| com.apple.WindowsContacts.client.exe | Syncs the device with Windows Address Book / Windows Contacts |
| com.apple.WindowsMail.client.exe | Syncs with Windows Mail |
| com.yahoo.go.sync.client.exe2 | Syncs with Yahoo |
Depending on your setup, some of these background processes might not appear. iTunes can start other background processes to perform various tasks like syncing and diagnostics. New functions might be added to these background processes in the future. You shouldn't disable these processes even when iTunes isn't open on the computer.