Enrico, there is no size limit for Aperture libraries.
If the copying did not succeed, there may be a problem with the contents of your library (a file with an incompatible filename, for example.) You'd better try to find out why, before you split your your libraries, for splitting may not solve the problem.
but it din't finish the work for a error.
What is the error message exactly?
How are you copying? Are your drives directly connected, or are you using a network to copy?
Are both drives formatted MacOS X Extended (Journaled)? If your destination volume still has the default formatting MS-DOS (FAT), there may be ambigious filenames and copy conflicts.
Can you see, what the last file that has been copied has been? Is there a partially copied library on the destination volume? Then inspect the image that should have been copied next, and look at the filename and if it can be opened.
I'm copying with copy past
Do you mean with "copy and paste"? Drag and drop from one disk to the other would be better - simply drag it with the mouse or trackpad.
You can also copy the library in parts. If you ctrl-click the Library and select "Show package contents", you will see a Finder window showing the folders inside. Create an empty folder on your destination disk, name it "copiedApertureLibrary.aplibrary", and then drag the folders - one by one - from the original library to the copy onto the other drive.
Enrico, as I suspected: The Finder cannot complete the operation because some data in your library cannot be read or written. That usually implies corrupted image files or videos, or filenames with control characters or ethnic characters (like in perché) in the name. Also characters used by the underlying unix shell are not a good choice for filenames, like "/" or "~" .
In this case try to copy in parts, so you can see which of the file inside the library cannot be copied. As I said above:
If you ctrl-click the Library and select "Show package contents", you will see a Finder window showing the folders inside.
- Create an empty folder on your destination disk, name it "copiedApertureLibrary.aplibrary",
- and then drag the folders - one by one - from the original library to the copy onto the other drive.
This way, you will see at which file the copying will stop. When you see the error message, see which files have been copied successfully, andcheck the filename of the next file, that could not be copied.
Then try to rename it in Aperture.
When you ctrl-click your Aperture Library and select "Show Package Contents", you will see a window like with folders, one is "Thumbnails". Open the "Thumbnails" folder, now you will see a mess of cryptic folder names. One of these folders will contain the broken thumbnail image.
Type ⌘F to launch a search and enter "thumb_dsc6192_face2.jpg" into the search field to find the file.
Or try to search the image "dsc6192.jpg" in Aperture and rebuild its thumbnail: If you can find the image, use the command "Photos > Generate Thumbnail".