That shouldn't be a problem, technically. But regarding FTC, that might cause an issue.

On Electrum:
Any old addresses were stored (more accurately: pre-generated) in your wallet and the funds should be received without any problem as long as the transaction went through.
You can also check all of the available addresses by showing the address tab: 'View->Address Tab'.

Vanitygen's main purpose if for creating personalized address, not to bruteforce private keys.

But I second this: RIP LBC 'after 104 more addresses'.
It's been dead for a long time though, there are only few users left who's actually "adding" a share (for the Puzzle).
Most are just brought there by curiosity and false hope.

He's using his own fork/version. Question is: if it is free, open-source or real, he didn't shared the link.

Is this the version that keychainX is talking about: Faster and Autonomous Large Bitcoin Collider upgrade?
'Coz I'm seeing the same users from that thread.

The difference is: those cloned cars and other knockoffs from China were exclusively distributed and sold inside the country.
There's a huge difference when the products have an international market or produced by a non local-based company.

OP however, didn't seemed to have a strong allegation against Inno3d (I'm not qualified to judge by the law though).

Could it be the blockchain headers, try to look for the "blockchain_headers" file inside the data folder (where the wallets folder is).
If it is 40mb or less and increasing in size, it is connected to a client, somehow your client has been trying to download it again before trying to sync the client.
If the servers list didn't have a text saying "connected to", there must be something wrong with your computer/electrum version.

Try to run it as administrator and/or temporary disable the firewall.

If you're willing to add low-high quality traffic, you can try to establish partnership/sponsorship with a well-known youtube crypto-related channels (with lots of subscribers and trending newly uploaded videos).
The sponsored channel should add a link to your site to every video description together with a short introduction to the offered services.
And if possible, add a short end credits saying "sponsored by 'your site' " or a thumbnail w/ a preview of the videos (as I noticed on some videos, regulations regarding this is kinda "unpremeditated" by youtube).

Try to contact VoskCoin (not affiliated with me, I'm just a viewer) if he's available or his channel A+~ed your expectations.

Depending on the channel, you might get a lot of prospective regular visitors.
And most importantly, this is probably cheaper than most Display ads APIs and services.

Okay:

• Build a Core2 Quad 2.666 GHz 12M (older version) PC with minimum specs. There are tons of super cheap secondhand units of these in the market, cheaper than an i7 but the performance for Criptonight V7 didn't have a very high gap.
  
• Download/install a (non-malware or scam) cryptonight miner with good number of userbase like: JCE Miner Cryptonight/forks
  
• Select a pool that mines the coin of your choice (either Monero[XMR] or Electroneum [ETN])
  
• Point your miner to the pool (check the pool's guide, some has an internal wallet, some haven't)
  
• And this is the most important part: plug your computer to your neighbors's garage without their consent in order to profit. (just kidding)

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If you're dead serious on "profiting" $2 a day, just install an Electroneum miner on your mobile phone and leave the internet connection and the app open in the background.
It will "generate" ETNs for you as long as your phone isn't turned off, it's not even mining at all (if they still didn't updated it).
That's it, you didn't even need to buy anything.

So, you want to utilize blockchain technology to your online portal as a database... forget it.

But you can develop an API which utilizes "signed message" as an ownership system which the user can only unlock his written article using his private keys. However, the data weren't stored in a fault-tolerant/uneditable way but users can use it without even registering an account, they can use the addresses as a donation/pay-to-open (needs more sophisticated techniques) address and the ownership issues can be easily solved (unless your site can't be trusted).

It's up to you or your developer on how you can implement such system, but theoretically, it's possible.

For example:

• 1) You online portal acts as a wallet and users can request an/some address/private key pair as his personal keys.
• 2) Everytime he 'save' his article the site will sign it using the user's session-entered (like MAW) private key, it will be saved as a text file in a signed message format and the signature shall be displayed for the user to copy (if he didn't have an account).
• 3) With this, a user can also import the private key to any wallet that can import keys then use the client to sign the article and paste the signature if it is 100% match to the saved article's signature.

But as they said, if you're planning to use blocks and POW as the database, it will going to be more stubbornly-unnecessary than my idea above.  
Nobody asked you why? Planning to start an ICO that advertises blockchain tech to online portals?

So it seems like you've misunderstood this part:
The comment is based on the OP's 3rd question which is: "Do we use master private key to sign every transaction?" he actually nailed it.

To put it simple, as you know it (Hierarchical Deterministic) HD Wallet has a Master Private key where all of your addresses's private keys were based from.
The client (ex. Bitcoin Core/Electrum/Multibit) where it was created or supported can restore all those required private keys to spend the previous UTXO, your client does that automatically for you.
The only backup you need is the Master Private or the SEED, each private keys are only optional.

Also, I think that there are more information provided in the comments from the link you provided (small fonts with numbers), look again.

Or... it was taken by a native who have no idea what Bitcoin is and used the container for something else.
The actual price (the paper wallet) was used to start a fire stove or turned into a paper plane and landed on someone else's roof.

Is this based on blockexplorer's report of the address' transaction history?
Do you have any physical access to the location in order to check if it was already taken?
Although sarcastic, my first statement can be true.

I know this will sound harsh: Leave the GPUs to the Gamers, Gaming industry and Graphic Artists;
Let them use the "Graphic Processing Unit" for computing "graphics" at a reasonable price.

Apparently, it's foreseeable that major digital currency's algorithm battle against ASIC manufacturers will either "let it go" or keep updated until one surrender which is will not be the case for those companies (there will always be another compatible shitcoin that will not fork).
Not ASIC manufacturer's defeat, not the coin hodlers either, but surely the GPU miners will be the most affected.

And the facts: Mostly all not-shitcoins can only be mined using ASICs or others are actively updated against ASICs and not GPU-optimized. Not centralized either, both are publicly available and the price between a single GPU and an ASIC isn't that high.
It's a Win-win for Bitmain, man this Chinese company needs to pay more taxes.

Overall, less GPU miners is for the greater good (just do the math)
In the future, most major coins will only be mineable using ASICs.
Believe me, I'm from the future  

Any solid proof to support this claim?

Shifting and shutting-down miners are 100% fact though (look at the graph in the OP, whoa, it dropped soo much w/ sarcasm), but this shouldn't affect the price that much.
This is totally something like FUD-related dip.

Vitalik must have realized the issue with GPU producers and the damages it has been causing to the gaming industry.
At least, one less GPU-dependent coin can help the affected industry(ies).
Also, as observed on Monero, changing or innovating new algorithm more often (due to ASICs manufacturer's marketing plan) can be a pain in the ass for their developers.

• Looks better without a background
• Or Personalized

---

...You're welcome.

Logitech owes you one for your free advertising (lol)

The "receive" tab isn't really necessary to receive the bitcoins from the particular transaction, it's only for reference and label/description.
did they linked a url of a blockexplorer showing the transaction?

The issue can be non-synchronized client, does the circle on the lower-right corner of your client colored red or green?
If red, it's disconnected and obviously the issue.

Blockchain.info's Mnemonic phrase isn't an actual Bitcoin Seed, it is only usable as a backup using the site's UI or compatible APIs.
If you didn't heard the news, the sites domain changed into blockchain.com but still accessible using the old domain name.

If you wanted to recover the old wallet, you just have to restore it to their site using the "forgot-password button" for old wallet backups: https://login.blockchain.com/wallet/forgot-password
The page displays: "If you have a legacy wallet recovery mnemonic saved enter it below to view the password and login link."
You should be able to restore your wallet from there.

Aaaaaand using "Pikachu" as an avatar will make you recognizable as a 12th-grader or a 30-year old geek, peace man.

---

Anyhow, I just wanted share these avatars in case someone needs it. Free for personal use only, under Creative Commons licence  

• Bitcointalk (We are Satoshi) - With transparent Background (10.7kb)
• Bitcointalk (We are Satoshi) - With Solid White Background (10.7kb)
• In Bitcoin We Trust - Version1 (17.1kb)
• In Bitcoin We Trust - Version2 (19.6kb)
• My Personal Avatar (Behind my current Avatar) Feel free to use it. (9.64kb)
• Lastly, you will receive more merit by using a female avatar (22.8kb), try it.

  ---

Could be a Mini Private key, starts with S and consists of 30 characters, he just added random symbols for security purposes.
From SC@jYMc/?1{=maGJ/*********(o<$x1!,'**********/W:,0wh%TwVxbq6X.]/#@GsA53, something like SCjYMc1maGJ**ox1**WhTwVxbq6XGsA53 can be extracted.

@andromeda46 does this ring a bell?

Or you're just drunk when you created that email.

Lol no, heard the news?

Although news and articles are the main Pump and Dump tools, this time it's a combination of P&D and "natural fear".
The news that I'm talking about is the Ethereum's upcoming mining reward reduction (google it if you want).
What they "fear" is the whole Ethereum economy will landslide after the implementation, which will never happen IMO.

So, I would say, this is not totally a Pump and Dump and if you're looking for profit, this is the best opportunity you have to stash ETH before it recovers in the next few months.

Your main (standard) electrum wallet is fine as long as it hasn't been compromised.
Creating another standard wallet is fine too, but don't sweep them in your imported wallet.

The reason for not-using that imported wallet is: the private keys of the addresses that you've imported came from another source.
Even from a reputable source (Chipmixer), the only user who must have the control over (who have seen) the private key(s) must exclusively be you.

By doing "import private keys", you're just including the address & prv key pair to your wallet, the source still have access to the prv key.
By "Sweeping" it, Electrum will make a transaction using all the tx inputs from the address pairs of that prv key, it will discard that key later, the balance will be transferred to your own (addresses) wallet, minus the transaction fee.

Are you using Windows?
Try to increase the Virtual Ram (Page file) to a higher value or 32GB, then restart your PC.

If you don't know how: Open searchbox/cortana, search for "advanced system settings" click "Settings..." under Performance.
Click Advanced tab and click "Change..." under Virtual Memory, uncheck "Automatically change paging file size for all drives" then, activate "Custom Size" put your desired value, press 'ok' then restart when prompted.