i'm working on windows 7 32 bit and i've no problems at all .... maby you can open it with Compatibility Mode and then windows vista or xp ?

And maby this will work..

1) Install HTC Sync_2.0.4 under Vista SP2 Compatibility mode. (Rightclick -> Properties -> Compatibility tab)
2) Download and unpack the 64-bit drivers as listed ( see topic link )
3) On the tattoo device browse to Settings –> Applications –> Development and tick the option to enable USB Debugging. Now connect the Tattoo to your PC via the supplied USB cable. It will now install, but miss the ADB driver.
4) Go to the Device Manager (eg through: Start menu -> Rightclick Computer -> Properties -> choose Device Manager). The missing driver will be listed with an exclamation mark.
5) Update the drivers by pointing to the folder you extracted the drivers previously.

Found at : http://www.mydigitallife.info/2009/...m-in-windows-7/comment-page-1/#comment-612254
1. Download -> HTCsync.zip

2. Install it.

3. Download one of these (depending if you got x86 or x64)

4. Extract the downloaded files to a folder.

5. Go to start -> Devices

6. Right click on your android-phone, go to Properties and then the hardware-tab.

7. Choose to update driver and select the location where you extracted the downloaded files in step 3.

8. Give me a hug and enjoy sync.
Dear SaabAero,

You deserve my hug :) I search the net from yesterday and there was no solution, but now you provide the secret :) Thank you!
However, update in win 7 driver for (I assume an earlier driver file) no as easy as cake :) Choose manually upgrade and then "You have a disk" After I browse the folder with the files the HTC sync started and connect to the phone.

So thank you again, now I enjoy my 1 day old tattoo
Actually you don't need a special downloaded driver.
You just need to choose manually update driver as SaabAero says, but then click "Let me pick" And choose My HTC. Worked for me :D
I struggled with HTCSync, finally got it to work. Worked fine for about 6 months and then stopped working again. Tried three versions with no success.

Finally resorted to Android-Sync - Installed easily with good instructions, found my mobile first go and has worked perfectly ever since. Only problem was that it suplicated all my contacts from the mobile to Outlook on the first sync, presumably because it didn't recognise they had already been synced using HTCSyn, but once that was sorted it was fine.

Try it.