Error 900 when adding a music library

The Sonos app can show Error 900 when your Sonos system is having trouble adding a new music library share to your system.

Error 900 in Windows

This error references a problem with the Windows Server service. When you see this error, it means Sonos is trying to create the music share, but there’s not enough Server storage space to complete the request. To fix this error, the Windows Registry must be modified to increase the stack size for the Server service.

Editing the Windows Registry is a delicate process and can be harmful to your computer if done incorrectly. If you’re unfamiliar with modifying the Windows Registry, please contact us for further assistance.

If you are comfortable making edits to your Windows registry to fix this, follow the steps below.

  1. Open your Start Menu and click Run.
    1. On newer versions of Windows, you may not see a Run button. You can instead open the Start Menu, type
      and then press Enter.
  2. Type
    and then click OK.
  3. Navigate to the following folder:
  4. Look for an entry called IRPStackSize. If it’s already present, skip to step 5.
    If the IRPStackSize entry is not present, follow these steps:
    1. Click Edit and select New, then click DWORD Value.
    2. Under Value Name, type
      and then click OK. Note that you must type
      exactly as it appears as it is case sensitive.
  5. Click IRPStackSize, click Edit and then click Modify.
  6. In the Data Value box, type a larger value, and then click OK. If no value is present, make sure the Base is set to Decimal, then set the Value data to 24.
  7. Restart the PC, then try to add your music library to Sonos once more.

Error 900 in macOS

If you’re using a Mac and you see Error 900 when trying to add or access a music share, please follow the steps in our article on “Computer could not be found” errors.

Still need help?

Our technicians can help over the phone or with a live chat. You can also ask questions and find answers with other Sonos owners in our Sonos Community.