This topic describes how to work around problems that arise when your project has thousands (or more) of files.
To fix this, create a file in your project folder called .noLock ( the leading . is critical, and that capitalization matters).
Additional information about the issue:
When Domino synchronizes your files with the server, it takes out a lock on all your project files to ensure they don’t change during the synchronization process.
If you have a large number of files, Domino runs into the operating system’s limit for the number of files that can be open at once.
The .noLock file tells Domino to skip its normal step of locking your files during synchronization. You must be careful not to change any of your project files while Domino is uploading or downloading them.