Cannot update framework nor MSE due to error 0x80070643 or 643

[marcosdipaolo]

You can see what's happening in the screenshots. Error 643 or 0x80070643 when trying to install Net framework or Microsoft Security Essentials. .
In the process i tried uninstaling MSE and installing the new version from the Microsoft's website but it didn't work and now i'm unprotected.
In the middle of the process I applied the "Take ownership" command to the ProgramData folder thinking that was a permissions issue but it didn't help.
I ran the System Update Readiness Tool and sfc /scannow. I remember having good results from sfc but the last results told me that there were some corrupted files that coudn't be fixed. SURT ran without any trouble.
I tried the FixIt from Microsoft but it didn't solve anything.

Edit: Here some updated info

I tried cleaning up Net framework with a cleanup tool from Aaron Stebner's WebLog.
Then i downloaded Net Framework 4.5 and installed without any issues.
The I tried to update to 4.5.1 and installation failed, same error.

Then I tried the Microsoft NET Framework Repair Tool but it didn't change anything
I send you some logs in case you need them

 

[marcosdipaolo]

Sorry guys but is this the kind of forum with mods reacting on a daily basis helping people? i've seen threads with people waiting more than a month for an answer