Asset Scan don't recognize new Software Versions

Asset Scan don't recognize new Software Versions

I'm using SDP and scanning 200 workstations with using network scan.
Now I see that for example software 'itunes' shows in SDP old version number.
I think it shows the version who was installed at the first scan.
I have checked all the assets with this software and all are up-do-date with newer versions.
 
A new scan of the assets shows no new entries.
 
Question:
how can I fix that?  (without deleting the workstation)
 
 

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