Edit: After placing the bootstrap.dat into clam folder, the progress of synchronization remains slow. Am i doing something wrong? Usually the way is to place the bootstrap.dat into user/appdata/roaming/clam (windows) and to restart the wallet, right?. I also tried to delete all userdata. Progress still slow.
Any idea?
I answered a similar question a few days ago:
First off, you need to stop and restart the client before it will notice the bootstrap.dat file.
Secondly, take a look at this screenshot. See the "importing blocks" in the lower left corner? That means the client is processing the bootstrap.dat file. Do you see that?
Thirdly, you wrote "Bootstrap.dat". The filename should be all lowercase. I don't know if that actually matters in all operating systems, but it does in Linux. If it isn't being found, try renaming it to be all lowercase then restarting the client.
Finally, I just updated the bootstrap.dat file. See this post for the link. If you use the torrent link you should be able to update your existing bootstrap.dat file to the latest version without having to redownload the whole thing.
I hope that helps.