Thank you for taking time to post this issue in Microsoft Q&A forum.
Nowadays I am having issues opening existing projects (…).
May I confirm that this issue doesn’t appear on any newly created project?
Please first try to clean the project cache files/folders by removing the hidden
.vs, bin and obj folders and then open the projects again.
If it doesn’t work, please try to repair Visual Studio from VS Installer.
Feel free to let us know if it works this time.
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