Not a valid integer value when opening Package Manager

[alexbalmus]

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After installing EMBT Dev-Cpp v6.3 (also happened using the previous version) using the installer bundled with the compiler, on Win10 x64, when opening the Package Manager I get the error displayed in the attached screenshot. After dismissing the error dialog, the Package Manager window opens but is not usable (fields disabled).

[glcjr]

I get this error as well when opening the package manager.