Configuring Support for Long Path Names in Altium Designer

Starting from Windows 10 version 1607, MAX_PATH limitations have been removed from common Win32 file and directory functions. However, you must opt-in to the new behavior by changing a registry key to enable support for actions when a file path with the file name exceeds 256 characters, such as:

• Opening a project from the connected Workspace.
• Making a local project available in the Workspace.
• Changing the folder path in an Outjob file.
• Generating outputs using an Outjob file or the Project Releaser.
• Saving a project as a project template to the Workspace.

1. Click Search (shortcut: Win+S), type regedit.exe and then press Enter.

   

2. In the Registry Editor, navigate to the following location: Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem.
3. Right-click the entry named LongPathsEnabled and select Modify.

4. Set the Value data to 1 and click OK.

   

   If the registry key does not exist, the entry can be added by doing the following:

   1. With the FileSystem folder selected, right-click in the empty space of the Name column where the registry keys are located, and select New » DWORD (32-bit) Value from the context menu.
   2. Name the key LongPathsEnabled and press Enter.
   3. Right-click the entry named LongPathsEnabled and select Modify.
   4. Set the Value data to 1 and click OK.

   This registry key can also be controlled via Group Policy at Computer Configuration > Administrative Templates > System > Filesystem > Enable Win32 long paths.

   Learn more about how to Enable Long Paths in Windows 10, Version 1607, and Later.

5. Restart the PC.
6. In Altium Designer, enable the System.LongPathsSupport option in the Advanced Settings dialog and restart Altium Designer.