After running 1.6.3 update, all Source tree installers fail with error: SourceTree -- Key not valid for use in specified state.

I was prompted to update source tree, and after uninstalling the old version the updated started reinstalling with version 1.6.3, but the installer crashes with the following message (copied from the windows event viewer): I cannot use or install any version of Source tree on this machine now!

The description for Event ID 10011 from source MsiInstaller cannot be found. Either the component that raises this event is not installed on your local computer or the installation is corrupted. You can install or repair the component on the local computer.

If the event originated on another computer, the display information had to be saved with the event.

The following information was included with the event:

Product: SourceTree – Key not valid for use in specified state.

(NULL)
(NULL)
(NULL)
(NULL)
(NULL)

the message resource is present but the message is not found in the string/message table

• <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
• <System>
  <Provider Name="MsiInstaller" />
  <EventID Qualifiers="32777">10011</EventID>
  <Level>2</Level>
  <Task>0</Task>
  <Keywords>0x80000000000000</Keywords>
  <TimeCreated SystemTime="2014-08-25T09:17:00.000000000Z" />
  <EventRecordID>38790</EventRecordID>
  <Channel>Application</Channel>
  <Computer>mustang.greenvalley.nl</Computer>
  <Security UserID="S-1-5-21-186282215-2137651597-1676229175-1009" />
  </System>
• <EventData>
  <Data>Product: SourceTree – Key not valid for use in specified state.</Data>
  <Data>(NULL)</Data>
  <Data>(NULL)</Data>
  <Data>(NULL)</Data>
  <Data>(NULL)</Data>
  <Data>(NULL)</Data>
  <Data />
  <Binary>7B33393939353745372D424231462D343938362D393638422D4637433541463743343743417D</Binary>
  </EventData>
  </Event>
  Binary data:

In Words

0000: 3939337B 45373539 42422D37 342D4631
0008: 2D363839 42383639 4337462D 37464135
0010: 43373443 7D41

In Bytes

0000: 7B 33 39 39 39 35 37 45

{399957E 0008: 37 2D 42 42 31 46 2D 34 7-BB1F-4 0010: 39 38 36 2D 39 36 38 42 986-968B 0018: 2D 46 37 43 35 41 46 37 -F7C5AF7 0020: 43 34 37 43 41 7D C47CA}