Q: Trying to log into my iTunes account and keep getting "unknown error occurred (-50)

Welcome to the Apple Community.

1. Quit iTunes.
2. Navigate to User > Music >iTunes > iTunes Media > Downloads
3. Delete the Downloads folder on your computer.
4. Open iTunes.
5. Choose Store > Check for Available Downloads.
6. Enter your account name and password.

Error 13, 14, 35 and 50 (or -50)

These errors are typically resolved by performing one or more of the steps listed below:

1. Perform USB isolation troubleshooting, including trying a different USB port directly on the computer. See the advanced steps below for USB troubleshooting.
2. Put a USB 2.0 hub between the device and the computer.
3. Try a different Dock Connector or Lightning Connector to USB cable.
4. Eliminate third-party security software conflicts.
5. There may be third-party software installed that modifies your default packet size in Windows by inserting one or more TcpWindowSize entries into your registry. An incorrectly set default packet size can cause this error. Contact the software manufacturer that installed the packet-size modification for assistance. Or, follow this article by Microsoft to reset the packet size back to the default for Windows:How to reset Internet Protocol (TCP/IP).
6. Connect your computer directly to your Internet source, bypassing any routers, hubs, or switches. You may need to restart your computer and modem to get online.
7. Try to restore from another known-good computer and network.

 

iTunes: Specific update-and-restore error messages and advanced troubleshooting