Hm. But it should work with Bitcoin core version 0.19.1, right? I am still getting the same error.  
  
With bfgminer (latest) it says "No servers could be used! Exiting."
 
and with cgminer: "No Stratum, GBT or Solo support in Pool 0 (IP:Port) unable to use"
 
Many users report that some bitcoin.conf changes fixed their issue and they were able to mine to bitcoin core 0.19.1. But I tried out all the fixes, none helped.

Many older threads told me to only use Bitcoin Core 0.19.1
I am starting it with

./bitcoin-qt --server

my bitcoin.conf looks like this:

daemon=1
server=1
rpcuser=(username)
rpcpassword=(password)
rpcallowip=127.0.0.1
prcport=(port)

I tried many different ports and many different username/password variations in the .conf and cgminer.
I once tried running bitcoind it via

sudo ./bitcoind --server

which starts just fine and then prints "wrong password attempt" or something like that in the log terminal window when I start cgminer with the correct rpc user/pass. Wrong password - but it's the correct one. Weird.

 
I start cgminer like this:
sudo ./cgminer -o http://127.0.0.1:(port) -u (username) -p (password) --btc-address (address)
Starting it wouthout sudo gives me a permission error on my mining devices.


What am I doing wrong? The username and password I use for cgminer are 100% the same as in the bitcoin.conf.
Thanks in advance for every kind help I can get!  
Edit:
When starting bitcoin core via

sudo ./bitcoind -server -rpcuser=(user) -rpcpassword=(password)

(Starting it via sudo is the only way for me to see the live log in terminal.)

Then quitting it again via
  
sudo ./bitcoin-cli -rpcuser=(user) -rpcpassword=(password) -stop

it accepts the user/pass combination just fine, prints "Shutdown: In progress..." in the terminal window and quits after a few seconds.  
There must be something wrong here with cgminer, right?

ok thanks.

but what about solo mining with bitcoin core 0.21.0? does it work again??

Good day everyone!
  
I have researched a lot about solo mining with cgminer and Bitcoin Core and have found people saying that only Bitcoin Core 0.19 supports solo mining with cgminer because of some technical details. Can't find the thread anymore where I have read this. But I think it could have been an outdated thread and the latest cgminer and Bitcoin Core versions may have already fixed that issue so that one can solo mine again?
  
I also found out that I need to use the startup command --btc-address (address) in order to actually receive mined Bitcoin to my wallet. Is that correct?
  
Am wondering if the current cgminer 4.9.2 version and Bitcoin Core 0.21.0 version work well together with solo mining Bitcoin? I am using a Raspberry Pi 4 with the latest Raspbian OS version and have the miners plugged into the USB ports. The miners itself work just fine, I have tested them with a Bitcoin mining pool and they are hashing away nicely.  
  
I know, I know. Solo mining is selfish and the probability of finding a block with outdated mining hardware is low. I plan on testing everything out with the solo setup first before I buy any larger amounts of miners to get into it more seriously. Don't want to find out that Bitcoin Core does not support solo mining anymore with cgminer and end up with useless brand new mining hardware. So I try it out first with low end miners.
  
1: Are there any other commands I should add besides -o http://localhost:8332 -u username -p passsword --btc-address address?
Are there any specific entries I should make for the bitcoin.conf file besides setting up a username and password and setting up the port with an entry in said file?
 
2: I have also read that a successfully setup cgminer with Bitcoin Core will display the textline "mining to (address)" in the cgminer window every few seconds, is that correct? What am I doing wrong if I do not see this message?

3: What startup commands do I need for Bitcoin Core for this solo setup besides -server (or is it --server with 2x "-"?)


 
Thanks so much for your help guys!
I hope other people google'ing the current versions of cgminer 4.9.2 and Bitcoin Core 0.21.0 + Bitcoin solo mining will find this thread with some helpful answers/a good tutorial made by someone nice in this thread.   Because I did find various different startup commands via Google for cgminer and am completely puzzled which of them I should use and which I should not use. (besides the -o, -u and -p).

I trade on Binance with maximum 125x leverage and recently did a couple of hundred percent gains a few times.
Quite nice.
 
But it needs some risk management, don't use too much of your money with cross margin.
 
In my opinion isolated margin mode is instant margin call. Cross margin gives some room for letting the price go against you without a margin call before going back to positive again.

I also do never use any stop losses because of stop hunting. It cries for instant position closure with a loss.
 
But everyone like he wants it.
 
I have traded on Bitmex before with 100x leverage only and my main problem was not the risk. It was getting in a position with limit orders, since it only went up $0.50 for a long time in sideways times.
With Binance I mostly do market orders, since my balance can afford such a little hit. I abandoned the "limit only for position opening"-train since I switched to Binance. Seemed way more fun in these volatile times to get in a position asap.
But for the people who like limit orders: Binance is much easier to get a position opened. Much more volatile. You can get in a limit opened position there very quick. Not as quick as a market order but still quicker than on Bitmex. 
  
(I am ready to get flamed to death right now, go ahead. )
  
By the way I come from trading times from 2013/2014 when OKex was named OKCoin and they had only 20x leverage. Kraken only had 5x. And BitMEX was the hot shit back then.
Those have been funny times I am telling you. Before I could buy on any exchange I panic bought my first Bitcoin on eBay haha. Way below $500, way below that.... I think I mined my first BTC in 2012 or 2011 or something.
Anyway getting a little off track with my text here.

I did heavily gamble on PrimeDice for a very long time. Had some big wins, some losses.
I want to gamble just a little bit there again but only with like 10k satoshi or something like that.
My days of depositing 0.01 - 1.00 BTC are long gone. Not doing that anymore because I don't want to chase any profits anymore. Just would like some dice entertainment.
Since it is impossible to send the amount of only 10k satoshi to PD and not lose 10k on fees I was wondering if anyone knows the stance of PD's lightning development?
Will they ever accept it?

Also another question: Is it planned to let users self decide the withdrawal fee and remove a minimum withdrawal amount so small money gamblers can still have fun over there?
 
Btw also using this PD bot that was heavily used (this "official" one) was great fun!
Even only with 100k satoshi and betting 1 satoshi I can have fun for hours and hours with it.
 
I know that I will lose the money I gamble there most likely but still it's nice to have some dice entertainment every now and then without being stressed about making a profit.

Also wondering about checking out Stake.com at least once. No idea if the games are any fun over there, I'm more of a classic dice guy.

That one must be an exchange cold wallet. Transaction happened within the last 12 months also. I bet it's Coinbase. Or Bitfinex.
 
Btw
 

not familiar with these kind of numbers that begin with "e", what does it mean?
I'm stupid I know. I'm also not very good at math. Would be happy to have explained why you wrote those "e"-numbers behind the addresses. Thanks!

edit I just went through the BTC Top 100 Rich list and found some that had over 1million BTC transacted. That's heavy.
Also sorry for pushing this thread slightly Off Topic.

Woah that https://www.blockchain.com/en/btc/address/1FeexV6bAHb8ybZjqQMjJrcCrHGW9sb6uF?offset=250&filter=6 address is filled with $300 million!
I thought this whole riddle was about 32 BTC?
Btw I am not into this cracking kinda stuff enough to participate into this. Just clicked through the posted addresses in this thread and found this HUGE wallet which a user above me posted.
 
Insane.  
I guess if this key is crackable, the reward is so insanely high because it is nearly impossible to crack.
I'd love to know the guy knowing the result to this riddle and get to know how to solve this lol. That'd be awesome.
Like "Hey dude you heard about this riddle I made with Bitcoin? You aren't into BTC anyway, so here's how to solve it...."
"Oh that sounds fun! No worries I won't participate in solving it. *Opens Bitcoin wallet and imports priv key*"  
 
By the way: Ever thought of where this huge stack of Coins might come from? Could the source be some illegal hacking stuff offering the coins for grabs via a riddle because they can't sell them anyway? (IF it is related to any riddle at all.) Could it be an exchange wallet not related to a riddle at all? Would be really interested in seeing some blockchain analysis here to get to know who owns/owned these coins and how they have been acquired. 2011 is a long long time ago.  
Or did Mark Karpeles forgot a paper wallet sitting in between his couch again?

Don't want to poop on the party but I did dump in Dec. :X (Read end of post)
I already feel bad about taking that profit.
 
To OP: To be honest nobody could have known when to dump because it looked like it could easily go to several hundred thousand. And psychology had us all with everyone saying "To the moon!" when we already reached the top, so we all waited for more. Except for some lucky people who got out at that point.
 
To make you feel better: I dumped my major holdings (not disclosing how much) already at around $2-3k just because one person wrote something.. Could have easily made a really stupid amount of money with those BTC I held for so long. But I didn't, only made some "small stupid amount of money" lol. That was stupid. Bought them way below $1000 But I still had X BTC left which I held because I did not care anymore until I was recommended to sell by a close person. After a long discussion I then sold.
 
Yes I am not a smart person but who cares. Took profit for Bitcoins which I bought way below for what I sold so I still made some money. Not the smart way to make money (relying on other people lol) but it somehow got the job done.
 
Just take care for your next investment. Maybe only invest what you can afford to risk. Because investing is risky as hell, it can turn out nice or you can lose a huge percentage of the original investment amount you put in, especially with these markets. Stressy as fuck, always making people sell bottoms.

edit: nevermind

I recently found a thread here with some sites where you can trade Stocks with only BTC as the main balance without having to convert to USD.
But the problem is: I don't know which one has the lowest fees.
And also one important requirement: I know that there are ways to trade stocks in a way where you can not get a position liquidated or even end up with a negative balance. I am searching for something like spot buying and selling stocks (was that called buying Equities? I forgot) with Bitcoin. Where you can not get force-liquidated and only experience a loss if you sell for a loss. It still can be displayed as a position too, if there is no real "spot buying" website for this case, but without any force-liquidation and also without leverage.
Also I can not find the thread anymore and would like to ask for your personal experience on a website recommendation since trying out every single one can lead to loss of money or just lots of time wasting because there are just too many sites offering this.
But I still hope there is a website offering exactly what I am searching for.
 
If anyone could help me also tell me your experience with that site, I'd be really happy to hear it!
 
Thanks a lot for all the help I can get here!

PS: I am a non US citizen. Am from Europe if that helps.
I also have read that not all results from Google are trustworthy theses days. Have also heard from WorldMarkets.io via Bitcoinist but the liquidity is just not there and the interface is kinda bugged for me.

We could also give exchanges the finger and start trading it here in this thread
But to be honest: I would love to see an exchange having CAP as it's main exchange coin instead of BTC. And way more merchants. But that is a pipe dream.

edit: topic can be removed. thank you.