The system cannot recognize the license anymore

Hello,

I have a problem with my license upgrade. I've upgraded the step manager S7 V5.5 to V5.6 SP2. I had only the upgrade software. I had 21 days for the trial to be upgraded. I didn't upgrade during this time. Now I have a problem. The system cannot recognize the license anymore. The message I get is "No valid license key found, the application will be closed". I tried to uninstall the STEP7 and to take out the license and put everything back, but the same problem. What can I do. Thanks for your kind help.

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Split from No valid license key found.

Hello Siemens Beginnerpm,

you need the suitable license for STEP 7 V5.6. You can install the license during the installation or after the installation of STEP 7 V5.6. If you have install the correct license and there are problem we recommend the following FAQs (links).

When you open STEP 7 Professional / Basic, why do you get the request to install the license even though you have installed the license?
https://support.industry.siemens.com/cs/ww/en/view/43184652

Why does a message appear in STEP 7 stating that there is not a license key present even though the relevant license key is installed?
https://support.industry.siemens.com/cs/ww/en/view/15293567

How do you restore defective license keys and authorizations?
https://support.industry.siemens.com/cs/ww/en/view/772175