S2550 Dead boot after flash

[copermine]

I've disconnected phone while upgrading firmware via kies and now s2550 won't start. I can't run download mode. It's black sceen only. Any ideas how to fix it without additional hardware?

[One_Hermit]

I've disconnected phone while upgrading firmware via kies and now s2550 won't start. I can't run download mode. It's black sceen only. Any ideas how to fix it without additional hardware?

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