Can't save my Toon Boom document, send help!

Hi guys.

I’ve got a problem when I was trying to save my works and then a dialog box came out and said “Error while saving animation set. Unable to access file (my_file’s_name).tbp.new.”

Please give me any solutions to solve this problem.
Best regard from me for you all.

Go into the menu-Edit-Preferences and make sure (on the General tab) that the location of the Global Library is a location you have access to modify.

Try saving to the desktop. If that fails, try it from a different user account
(Mac/Windows).

Here is the method ,You can have a look:
public static void SaveDocumentFile(REDocument document, string filePath);
public static void SaveDocumentFile(BaseImage image, string filePath, BaseEncoder enc);
public static void SaveDocumentFile(List images, string filePath, BaseEncoder enc);
public static void SaveDocumentFile(REDocument document, string filePath, BaseEncoder enc);
http://www.rasteredge.com/how-to/csharp-imaging/imaging-saving-printing/