HTC Desire cannot connect with HTC Sync

I recently received an HTC Desire as a gift with no SD card. It was updated to Froyo. I'd like to update it further to Gingerbread, however I cannot get any version of HTC Sync to recognize my phone.

• I've tried several versions


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  I've disabled firewall and antivirus

  
  


• 
  

  I've run HTC Sync in compatability mode and as administrator

  
  


• I've rebooted both phone and PC


• I'm sure I've tried other things that I forgot to list.

The standard answer to this seems to be 'install the HTC sync version that is on your SD card', but I don't have the original card. I have been unable to find out which version of HTC sync that was originally included.

Does anyone know which version og HTC Sync I need for my HTC Desire to connect?