AutoCAD is a powerful computer-aided design (CAD) software developed by Autodesk Inc., widely used in various fields such as architecture, engineering, and construction for creating 2D and 3D designs.

If you're encountering issues with activating your AutoCAD 2015 version after entering the product key, follow these steps to resolve the problem:

1. Ensure that your system meets the minimum requirements for running AutoCAD 2015.

2. Check if there are any updates available for AutoCAD 2015 and install them.

3. Launch Autodesk Activation Manager by double-clicking on its icon or searching for it in Start/Programs (Windows) or Applications/Utilities/Autodesk/Activation (Mac).

4. Follow the prompts to connect your computer to the internet, even if you're using a proxy server.

If after following these steps, you still encounter an activation error when entering your product key:

1. Check that you have entered the correct product name and version in the lookup tool.

2. Ensure that your AutoCAD 2015 software is genuine and not trial or demo versions.

To activate AutoCAD 2017 using a serial code:

3. Click on Generate once (a code will appear).

4. Copy the generated Activation Code and go back to the AutoCAD 2017 installation page.

5. Paste or type in the Activation Code received earlier into the activation code field as shown below, then click Next.

By following these steps carefully, you should be able to successfully activate your AutoCAD software without encountering any further issues related to product key recognition or serial code entry.

Autocad activation code 2015