Hi!
I found this:
For all people having trouble installing SE Smartphone PC Suite On WindowS Vista, here is a workaround until SE release a fully Compatibile Vista Version.....

Follow These Carefully:

- Run the installation program
- When you get the error, do NOT click OK, but leave this open.
- go to localsettings/temp
- find a new folder with the most recent date and time (from when you extracted it)
- copy the MSI files to your desktop
- Use Orca.msi (http://www.brentnorris.net/orca.msi) to edit the Sony Ericssion PC Suite.msi file
- Edit a line called Launchcondition - remove the first line
- Edit a line called file remove the first 2 lines called msxml2.dll & msxml2r.dll (old verisons you have to remove them or the installation will halt as the system won't be able to overwrite the newer files in Vista)
- Save
- Run the Pc Suite.msi file and enjoy a full installation
- Download m-Router installer http://developer.intuwave.com/Downloads/m-Router & run it using Win XP Sp2 comptability Mode and with administrator Previliage.
- Connect your phone to the PC, check device manager to make sure all phone drivers are loaded and installed properly, if prompted always choose automatically locate.
- Restart your PC
- Voila you have a full working Smartphone PC Suite working On Windows Vista!
Thanks.