You can't. You can enable pruning which means that as the blockchain is being downloaded, once the blockchain reaches a certain size (which you set), Core will begin deleting old blocks in order to maintain that size. However you will still end up consuming the bandwidth and time required to download and verify the entire blockchain.

To enable pruning, just add
to your bitcoin.conf file.

Make sure that digital ocean itself is letting you receive traffic to port 8332. I know that with AWS that you need to configure some security settings of the VPS itself outside of its OS to allow traffic to certain ports.

Blockchain.info's wallet can be extremely buggy and is poorly written. If you truly want your Bitcoin to be safe and to use a legitimate properly written wallet software, you should use a desktop wallet like Electrum or Bitcoin Core.

Your Bitcoin cannot simply disappear without there being a transaction sending it away from your wallet. If it is "disappearing" then there is probably an issue with your wallet software.

As for Bitcoin being sent to the wrong address, there are malware that will replace any address you copy with the address of an attacker so you end up sending Bitcoin to the wrong place. You should make sure that your computer does not have a virus.

The invalid header size error is not related to the block parsing. Rather that is because you are probably using Bitcoin Core 0.14.0 which is incompatible with Armory 0.95.1. If you are using Bitcoin Core 0.14.0, you should downgrade to 0.13.2. Once you do that, try rebuilding the Armory databases as well (although it shouldn't matter). If it still fails after that, you may need to redownload the blockchain.

Go to File > Settings and uncheck "Let Armory run Bitcoin Core in the background". Stop Armory. Start Bitcoin Core. Start Armory again.

blockr.io constantly has issues like this. It is probably due to some error on their node. This happens quite frequently. I would suggest that you use a different block explorer.

Just wait a little longer. The admins are the only ones who can unlock accounts and it takes a considerable amount of time to ensure that the person trying to recover an account is in fact the owner of that account.

That change was added in May 2015 after the forum was hacked.

You can't use greater than 0.14.0 with 0.95.1. You should make your own thread about this and post the armorylog.txt and dbLog.txt files.

Segwit is a block size increase. The size of the "block" p2p message can be larger than 1 MB after segwit activates.

No it isn't. The miners can't just activate any arbitrary consensus rule unless all users follow them and use that alternative client. Given that right now most full nodes are running some version of Bitcoin Core, if miners start using an alternative client supports a block size increase through a hard fork, they will be mining on a chain that few people use.

Then there is no problem and you can ignore the warning and tell your antivirus that it is a false positive.

A node can use the mempool message to request the txids of all of the transactions in another node's mempools. It can then ask the node for all of those transactions. Bitcoin Core 0.14.0+ will also save the mempool to the disk before it shuts down so it will populate its mempool from the saved data.

There are no addresses for P2PK. Most wallets and block explorers will just show them as a normal P2PKH address because it is easy to make that address and sending to that address will still allow the owner of that public key to spend their Bitcoin. Since the address is based on the hash of the public key, you can't make a P2PK script with just an address, you need the full public key.

As long as you have verified the binary when you downloaded it from bitcoin.org, it is safe and legitimate. Antivirus software will often flag Bitcoin Core as a virus because it contains mining code (to allow you to mine on testnet and regtest) and looks for a wallet.dat file (that's the wallet file that Core uses and creates).

It may be possible that you were scammed. It seems that scam clones of Bitcoin blender were made so you need to make sure that you used the actual service and not a fake.

Your transaction is confirmed; it cannot have multiple confirmations and yet be unconfirmed, that's an oxymoron. You don't need to do anything like CPFP or RBF because that is not going to help, your transaction is already confirmed.

If you do not see your transaction in your wallet, that is a wallet issue, not anything to do with your transaction or the Bitcoin network. Your Bitcoin is fine even if your wallet does not show the transaction. Since it is already confirmed, you won't be losing any money.

The issue is with your wallet. What wallet software are you using?

I think they only do things on request, not mass producing miners like Bitmain does.

The mining hardware cannot be made to not support segwit. Segwit is a software thing, not hardware. The hardware does not care about the consensus rules and segwit does not change anything about the mining algorithm. Bitmain cannot just "make a miner without segwit support".

I suppose you are talking about asicboost, but you clearly don't understand how it works or what it does. Asicboost works even with segwit activated. The hardware aspect of asicboost does not care about segwit nor does it care about the overt or covert methods. The hardware circuitry is the same. What matters is the software, and software can be easily changed.

A hash is a one-way mathematical function which converts arbitrary length data to a fixed length piece of data. Hashes are usually unique so they are used as identifiers and for indicating whether data has changed. The transaction hash is the hash of the transaction and is used as an identifier for that transaction; it is also called the transaction id (txid). The txid of your transaction is b29c456635c42d5f71054cefc8a61eae46685daae338c9788b355a60c77558ca. The link you provided is to a block explorer which displays the details for blocks and transactions.

No. A malicious miner cannot force a consensus rule change or violate any of the consensus rules.

Bitfury does.

Bitmain miners do work with segwit. Making hardware that wouldn't is not illegal by any laws. There are no laws governing the policies and protocols in Bitcoin.

The transaction is confirmed. If it does not appear in bitkong, then that is an issue with them. Contact their support.

This topic has been discussed multiple times already. Please use the search function or google and read up on the subject.

There are no known ways that quantum computers will break sha256.