I got quite a mess after downgrading from 2009 SP5.1 to SP4.1.

I have lost several programs/folders from C:\Program Files (x86)  after downgrading.

I run uninstall SW2009 x64 SP5.1 from Control Panel -> Programs and Features.

After that also installed SP4.1 and upgraded SW2010 to SP4.0.

Vista still starting but have to reinstall almost everything under 32 bit.

I hope this is only for me.

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More info: Got an error message from another program: "The feature you are trying to use is on a network resource that is unavailable."

Edit2: Java Virtual Machine missing ...