📦 Installing Oracle XE and Connecting with SQL Developer: From Download to Troubleshooting

Whether you're setting up a local Oracle database or connecting to it via SQL Developer, this guide has you covered—from the official installer to resolving common connection errors like ORA-12541.

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🔽 1. Downloading and Installing Oracle XE

🔗 Official Download Link

Access Oracle’s official site to get the latest Oracle Database Express Edition (XE):

👉 https://www.oracle.com/database/technologies/xe-downloads.html

🛠 Installation Steps (Windows)

1. Download the .zip or .exe installer.

2. If needed, extract the files and run the installer as Administrator.

3. During installation:

   • Set a password for the SYSTEM user.

   • The default SID will be XE.

4. Wait for the installation to finish. Oracle services will be configured automatically.

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🧭 2. Checking if Oracle Installed Successfully

• Press Win + R, type services.msc, and look for these services:

• OracleOraDB...TNSListener

• OracleServiceXE

If both show as Running, you’re all set!

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🛠️3. Did you download SQL Developer separately?

Oracle XE no longer includes SQL Developer by default. You need to download it manually:

• Official SQL Developer download: link
  Make sure to get the version with JDK included, if possible.

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🧩 3.1. Did you extract it correctly?

• SQL Developer comes as a .zip file. You must extract everything to a folder with no spaces in the path, like C:\SQLDeveloper.

• Do not run it directly from inside the .zip file.

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⚙️ 3.2. Check your Java (JDK) version

• SQL Developer requires JDK 8 or 11.

• If you downloaded the version without JDK, the application may crash when starting.

• Tip: download the version labeled “with JDK included” to avoid issues.

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🧼 3.3. Clear old settings

If SQL Developer opened before but no longer launches:

• Close SQL Developer.

• Go to:
  C:\Users\YourUsername\AppData\Roaming\SQL Developer

• Rename or delete the system... folder.

• Try launching the app again.

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🔐 3.4. Antivirus or security policies

• Some antivirus tools or network policies might block Java or SQL Developer itself.

• Try running it as Administrator.

• In corporate environments, there may be restrictions in place.

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🧪 4. Creating a New Connection in SQL Developer

1. Open SQL Developer

2. Click on "+" New Connection

3. Fill out the fields like this:

4. Click Test.
   If the result is "Success" in green, click Connect 🎉

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❌ 5. Common Errors and How to Fix Them

🔴 ORA-12541: TNS: No Listener

Error:

ORA-12541: Cannot establish connection. No listener on host localhost port 1521

Solution:

1. Open Command Prompt as Administrator

2. Run:

lsnrctl status

If it says the listener is not running, start it with:

lsnrctl start

If you get “command not found,” navigate to the Oracle bin directory first:

cd C:\app\yourname\product\21c\dbhomeXE\bin lsnrctl 
start

Tip: Run where lsnrctl to find the exact path.

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🔴 ORA-01017: Invalid Username/Password

Error:

ORA-01017: invalid username/password

Solution:

• Make sure you're using the correct user (system, hr, etc.)

• Double-check the password (it's case-sensitive)

• To reset the password (if needed):

ALTER USER system IDENTIFIED BY newPassword;

(you can run this using SYSDBA if necessary)

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🔴 Connection Timeout or Refused

Solution:

• Ensure your firewall isn’t blocking port 1521.

• Restart the services:

• OracleServiceXE

• OracleOraDB...TNSListener

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🗂 6. Finding the Oracle Installation Path

If you're unsure where Oracle is installed:

1. Open services.msc

2. Right-click on OracleServiceXE > Properties

3. Look under “Path to executable” to find the full install location

Alternatively, search for “SQL Plus” in Windows—if you find it, Oracle is installed and accessible.

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✅ Conclusion

With Oracle XE properly installed and SQL Developer configured, you're now fully equipped to explore local Oracle development with confidence. From setting up your first connection to resolving listener issues and common authentication errors, this guide has your back.

Remember: even if you run into problems like ORA-12541 or password errors, they’re usually quick to diagnose and fix with the right steps.

You're ready to dive into queries, procedures, and all that Oracle has to offer — enjoy the journey!

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