SQL Developer 4 Hangs on Startup

Question

SQL Developer starts with the splash screen, then opens a larger window (leaving both open) and then hangs there.
I've seen several threads like the following:
https://community.oracle.com/message/11326869#11326869
https://community.oracle.com/message/11127183#11127183
I'm running Java 7:
2014-01-29 13:54:55                                          
D:\oracle\product\11.2.0\client_1\sqldeveloper               
» java -version                                              
java version "1.7.0_13"                                      
Java(TM) SE Runtime Environment (build 1.7.0_13-b20)         
Java HotSpot(TM) 64-Bit Server VM (build 23.7-b01, mixed mode)
2014-01-29 13:56:12                           
D:\oracle\product\11.2.0\client_1\sqldeveloper
» $(gcm java).Path                            
C:\Program Files\Java\jdk1.7.0_13\bin\java.exe
I've completely deleted my %USERPROFILE%\AppData\Roaming\{sqldeveloper|SQL Developer} directories.
I'm running from my D:\ drive.
I've modified the %USERPROFILE%\AppData\Roaming\sqldeveloper\product.conf and pointed it at various JDKs with various results - as expected Java 6 flat doesn't work. Older Java 7 doesn't open the blank screen but hangs.

Answer 1

1.7.0_13-b20 is old, and is that a beta? We're testing and supporting with version 1.7u45 as a minimum.
You don't need to update your JDK - just download the Windows copy of SQLDev 4 that includes the JDK and you should be good to go.
The other thing you could try is to run it from your C:\ drive in case there's some weird write permissions issue going on.