Please wait ... forever

The solution !

Just managed to fix the problem and want to share it because there is nothing in the internet and Garmin forums.
Also Garmin support is completely useless ... out of space ...

1. Ensure you are close to your PC (in my case windows 7 64 bit) with USB garmin stick attached;
2. Detach garmin USB stick;
3. Restart PC
4. Attach USB stick
5. Replace watch's battery !
5.1 Open battery cover carefully.
Important !!!
Buy a good battery from some of the best brands - Panasonic, Varta, Energizer with a fresh man. date ...
Be careful when you open/close the battery cover. There is an red O-ring so it is important not to break it. If that happen - your watch will be not usable because it will start leaking. That ring is not selling separately.
6. Close battery cover carefully.
You should see the same message "Please wait..." but not blinking.
7. Stay close to PC, click Sync button in Garmin Express.

The sync should work but the latest sessions maybe will be lost.
The watch should look just it is hard reseted, so you will need to configure it again.
That is all, you watch is back to life.

Some notes:
All that seems to happen because of low battery and not successfully finished sync or other operation. In my case there were no indication that battery is low. Also my second problem was i bought a bad quality battery with low voltage so always check voltage before put it into the watch - should be >3.2V
If you have any other problems with sync, connect ... it is very possible your battery is low.

Clarification

Just to clarify kristian_kostov's statement, If you do get blinking, it is likely that the replacement battery is bad.

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Kristian_kostov said:
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You should see the same message "Please wait..." but not blinking."
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