I have 2 WD External Hard Drive Im trying to copy files from one to the other it wont let me because its read only..If i Reformat the one with the files so i can copy it using my imac would i lose my files in there?
Yes, formatting erases all data. What format are they using now? They may be in NTFS and then you could just download NTFS-3G and get read and write access to NTFS volumes