Hello. I'm writing to share some hard-won lessons about this installation process that are specific to Windows 7 64-bit. First of all, it should be known that the port of Oracle from 32-bit to 64-bit is not, in my opinion, complete.
Here's what you have to do:
There are two .zip files that you will download (currently from Oracle Database Software Downloads | Oracle Technology Network | Oracle ):
Extract both of these .zip files to the same folder using the "extract all" Windows Explorer right-click menu pick. It will ask you if you want to merge the files. Respond with yes.
The installation comes with its own version of Java which apparently has bugs in it. The installation script will not work as it is. It will mysteriously fail without any meaningful log messages. The window just disappears. Even clicking on buttons in the dialog box will make it inexplicably vanish. See other discussions on this forum which are now archived (which is why I'm not simply responding to one of those). To get around this, you will need to use a more recent version of Java. I used the 64-bit version of jdk1.8.0_05. To get the shortened DOS version of this path, I issued the following cygwin command:
$ cygpath --windows -d "C:\Program Files\Java\jdk1.8.0_05"
Next, in a DOS window (not a Cygwin window!), cd to where the setup.exe file is that you've extracted from the downloaded .zip files (the Oracle database installation downloads), and type:
setup.exe -jreLoc C:\PROGRA~1\Java\JDK18~1.0_0
This tells setup to use your version of the JDK, rather than the buggy version included in the Oracle 11g database installation download.
I don't personally have a "My Oracle Support", so on Step 1 of 9, I unchecked the "I wish to receive security updates via My Oracle Support", and clicked on next. An intimidating window will pop up requiring you to check a check box labeled, "I want to remain uninformed of critical security issues in my configuration". Click on Continue.
On step 2 of 9, check the radio button for "Create and configure database". Step 3 of 9, I selected Desktop Class. On step 4 of 9, I changed the Oracle base to "C:\cygwin\home\lylez\oracle", and accepted the other defaults (such as "Enterprise Edition"). You may wish to accept all the defaults; that's up to you. Select an administrative password (and write it down) and click on Next. Then click on Finish.
A window entitled, "Database Configuration Assistant" will pop up. It is imperative that you click on the oval-shaped "Password Management" button on the lower right to select passwords for the various sample accounts, and to unlock them. Otherwise, there's no way (that I know of) to set the passwords, and you'll have a big useless installation, at least as far as experimenting with existing databases goes. I recommend that all of the accounts be unlocked, and I personally used the same password for all of them (this is only for practice on my own desktop - you may wish to be more secure if it's being done for a corporation). I copied the password to the clipboard in notepad so that I wouldn't have to type it over and over again. Then click on OK, and then Close. The database should now be successfully installed. All of this takes a long time, so don't be discouraged.
Now, when you attempt to launch PL SQL Developer, it will ask you for a JDK. This is another source of misery. If you give it the 64-bit JDK, it will reject it, without telling you why, and it will stay in rejection mode until you give it a different path, even if the contents of the folder you gave it have since changed. You must instead give it a 32-bit JDK version, but it's not enough to simply provide it with a 32-bit java.exe file, you must provide the entire JDK directory and all contents. I copied my 32-bit JDK directory from my other computer, that is, the jdk.1.8.0_05 directory and contents, and gave that path (C:\Program Files\Java\jdk1.8.0_05_32bit is what I named it) to the PL SQL dialog box. Then it will work. At least, it did for me.
To create connections in PL SQL Developer,click on the add connection button (the paper symbol with the green plus sign on it), and give it a name. To create a connection to the sample hr database, give the username as hr, and give it the password you typed in for it in the Password Management window mentioned two paragraphs above in this posting. For the SID, you must change it from xe to orcl. You may also want to create a connection to sys. Do the same things as before, but this time, select "SYSDBA" in the drop-down box next to Role. For a sysman connection, I used the default role. Same with system.
I never could get the 12c database to install. It kept running into mysterious Perl errors.
Best of luck.