We apologize for our extended outage period. We are working very hard to ensure our services return 100% as soon as possible. As we mentioned previously, the outage was caused by a bug in some database handling code. Please rest assured that your wallets are safe and this outage does not affect the security of funds or the completion of executed transactions.
Unlike other services that have ownership over private keys, Blockchain is superior because it allows users to access their private keys, thus enabling them to have access to their funds under circumstances such as this. It is very important for us to emphasize how crucial it is that users make regular backups of their wallets. Doing so will allow users to import their funds into a wallet client such as MultiBit and therefore avoid the headache and stress of being unable to access their funds, for whatever reason.
After the import, MultiBit then replays the blockchain from the replay date to find the transactions for the new private keys. For blockchain.info wallets the blockchain must be replayed from the first block. This can take up to an hour on a wifi connection (depending on the speed of the computer you connect to). It is best just to leave MultiBit to sync the blockchain on its own.
If you don’t have a wallet backup, please fill out a helpdesk request here.
Thank you for your patience. We will continue to communicate throughout our resolution of this issue.