To Install SPSS Statistics 25 and higher on Windows:
1. Visit the SPSS Statistics Tigerware webpage.
2. Click the download button according to what System Type or Bit Operating System (32 or 64) the user has.
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Note: Information regarding 32 and 64-bit architecture, including how to determine which one your operating system uses, can be found in the GROK article: Windows: 32-Bit vs. 64-Bit.
3. If using Chrome, the download will commence automatically and upon competition of the download, the file will be linked to in the bottom left corner of your window. If using Firefox you will have to click Save File in the dialog box that will appear. (More on web browser standards can be found here: Web Browsers: LSU Overview (ITS Recommendations))
4. Regardless of your browser preference, the downloaded file can be found in your Downloads folder. Once located, select the file.
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Note: If prompted, select Yes to allow changes to be made to your computer.
5. After selecting the file, the InstallShield Wizard should open and it will begin to install. When it is done, it will close and the Licensed Materials window in the wizard will open. Click Next to continue.
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6. After clicking next, the License Agreement will appear. Click "I accept the terms of the license agreement" after reading the License Agreement. Click Next to continue.
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7. The Essentials for Python will appear in the wizard. Yes is chosen by default. Click Next to continue.
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8. The License Agreement for Python will appear next. Click "I accept the terms of the license agreement" after reading the agreement. Click Next to continue.
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9. A Software License Agreement will appear after that. Click "I accept the terms of the license agreement" after reading the agreement. Click Next to continue.
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10. The user will be prompted to where he/she wishes to save the program to. To change the Destination Folder, click Change. Click Next to continue.
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11. The program is ready to install. Click Install.
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12. The program is done installing. Click Finish.
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13. SPSS Statistics should now open up. From there, choose Authorized user license. Click Next to continue.
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14. The Enter Codes window will open up. Put in the authorization code in the blank provided and click Next to continue.
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15. The Internet Authorization Status window will open up. When the authorization is successful, click Next to continue.
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16. The authorization is now complete. Click Finish.
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Referenced from IBM