Finder error code -43

Hello,
Today I was trying to copy some files (including some folders and aliases) from my hard disk to my Dropbox folder that I have in my Finder. I wanted to copy some files into my Dropbox via Finder, because I consider that more convenient than uploading via my internet browser. Everything went well until about 80% of the files were copied. Finder gave me an error code -43, saying it was unable to locate some of the files or it's destination (I'm not very sure what the frase exactly was, it was a confusing message anyway). What does this error -43 mean and what can I do to fix this?

Finder error code 43 simply means the file was not found. It's difficult to track this down because it can mean "file corruption" (file name not found because of corruption) or it can mean the buffer was full while you were copying to Dropbox. Try copying fewer files at once rather than all together.

Error Code

I was getting that message or something close every time I tried to copy files/folders on an external hard drive. I couldn't unmount the disk. Turning everything off I could reboot and immediately unmount the external and run the repair in Disk Utility.

Not really sure how you could unmount the main hard drive, but you might just try Disk Utility Repair after restarting the Mac. You might have to boot from an external source.
I also have had issues of the type of format the HD or external is in. Using a search program for duplicate files. I'd get error messages because I'd have the same file with .JPG & .jpg


I'm no Super User, so my advice might be worthless. But I had to play around because that external had all my pictures and and music. I had to find the answer.