Hello,
Verify that you (or the user account you're logged in with) is the owner of the folder. Even if you granted full control to all users, ownership might still be an issue. To change ownership:
Right-click on the folder > Properties > Security > Advanced > Owner > Edit > Choose your user account and check "Replace owner on subcontainers and objects" > Apply > OK.
Sometimes, even with proper permissions, Windows User Account Control (UAC) may prevent saving due to lack of administrative privileges. Try running your application as an administrator.
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