JabRef 4.3.1
Mac OS X 10.12.6 x86_64
Java 1.8.0_191

Steps to reproduce:

I am trying to open my .bib file (created in BibDesk) in JabRef and keep getting these errors.

Opening: /Users/laurabellows/Box Sync/Home Folder leb58/Sync/Research/Literature/Bibliography.bib
Uncaught exception occurred in Thread[JabRef CachedThreadPool,6,main]
java.lang.IllegalArgumentException: The field name 'id' is reserved
at org.jabref.model.entry.BibEntry.setField(BibEntry.java:414)
at org.jabref.model.entry.BibEntry.setField(BibEntry.java:445)
at org.jabref.logic.importer.fileformat.BibtexParser.parseField(BibtexParser.java:574)
at org.jabref.logic.importer.fileformat.BibtexParser.parseEntry(BibtexParser.java:539)
at org.jabref.logic.importer.fileformat.BibtexParser.parseAndAddEntry(BibtexParser.java:237)
at org.jabref.logic.importer.fileformat.BibtexParser.parseFileContent(BibtexParser.java:203)
at org.jabref.logic.importer.fileformat.BibtexParser.parse(BibtexParser.java:144)
at org.jabref.logic.importer.fileformat.BibtexImporter.importDatabase(BibtexImporter.java:72)
at org.jabref.logic.importer.Importer.importDatabase(Importer.java:88)
at org.jabref.logic.importer.fileformat.BibtexImporter.importDatabase(BibtexImporter.java:66)
at org.jabref.logic.importer.OpenDatabase.loadDatabase(OpenDatabase.java:73)
at org.jabref.logic.importer.OpenDatabase.loadDatabase(OpenDatabase.java:52)
at org.jabref.gui.importer.actions.OpenDatabaseAction.openTheFile(OpenDatabaseAction.java:235)
at org.jabref.gui.importer.actions.OpenDatabaseAction.lambda$openFiles$2(OpenDatabaseAction.java:175)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

Can only load style files: Preview
Opening: /Users/laurabellows/Box Sync/Home Folder leb58/Sync/Research/Literature/Bibliography.bib
Uncaught exception occurred in Thread[JabRef CachedThreadPool,6,main]
java.lang.IllegalArgumentException: The field name 'id' is reserved
at org.jabref.model.entry.BibEntry.setField(BibEntry.java:414)
at org.jabref.model.entry.BibEntry.setField(BibEntry.java:445)
at org.jabref.logic.importer.fileformat.BibtexParser.parseField(BibtexParser.java:574)
at org.jabref.logic.importer.fileformat.BibtexParser.parseEntry(BibtexParser.java:539)
at org.jabref.logic.importer.fileformat.BibtexParser.parseAndAddEntry(BibtexParser.java:237)
at org.jabref.logic.importer.fileformat.BibtexParser.parseFileContent(BibtexParser.java:203)
at org.jabref.logic.importer.fileformat.BibtexParser.parse(BibtexParser.java:144)
at org.jabref.logic.importer.fileformat.BibtexImporter.importDatabase(BibtexImporter.java:72)
at org.jabref.logic.importer.Importer.importDatabase(Importer.java:88)
at org.jabref.logic.importer.fileformat.BibtexImporter.importDatabase(BibtexImporter.java:66)
at org.jabref.logic.importer.OpenDatabase.loadDatabase(OpenDatabase.java:73)
at org.jabref.logic.importer.OpenDatabase.loadDatabase(OpenDatabase.java:52)
at org.jabref.gui.importer.actions.OpenDatabaseAction.openTheFile(OpenDatabaseAction.java:235)
at org.jabref.gui.importer.actions.OpenDatabaseAction.lambda$openFiles$2(OpenDatabaseAction.java:175)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)