I am new to Ethereum. I have the v.0.8.7 client. It is fully synchronized with the blockchain (see screenshot below: last block seen a minute ago).
I am basing myself on this post.
If I understood correctly, my Client is currently synchronised with Morden (the article really does not explain things in a noob-understanable manner). So I have to swich to Ropsten.
I entered the commands specified at the bottom of the article, and get the following error.
dyn907-72:~ me$ ls /Users/me/Library/Ethereum/testnet/ chaindata keystore testnet_genesis.json dapp nodekey geth nodes dyn907-72:~ me$ geth --datadir /Users/me/Library/Ethereum/testnet init testnet_genesis.json I1122 14:01:12.203789 ethdb/database.go:83] Alloted 16MB cache and 16 file handles to /Users/me/Library/Ethereum/testnet/chaindata Fatal: failed to read genesis file: open testnet_genesis.json: no such file or directory dyn907-72:~ me$