The day I received Windows 10, everything seemed to work. The next day Microsoft Solitaire Collection won't open . I tried to uninstall and reinstall it but there was no app. When I went to the store to install it, it said it was installed already.

Suggest you to run the Windows 10 app troubleshooter and check.

http://windows.microsoft.com/en-us/windows-10/run-the-troubleshooter-for-windows-apps

If the issue still persist, perform method 2.

Method 1: Reset the Windows Store cache.

Follow the steps to reset the Windows Store cache.

Press Windows Key + R key.

Type wsreset.exe and press Enter Key.

Your Windows Store cache will be reset. Check if the is resolved.

You may also refer the Microsoft help article and check.

Why can’t I find or install an app from Windows store.

http://windows.microsoft.com/en-US/windows-8/why-find-install-app-windows-store

Note: The steps for Windows 8/8.1 applies to Windows 10 as well.