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Mysql Reading from the stream has failed

I have tiny exe's, I am developing with c# the size is max 100kb - 500kb.
A 3rd party application opens these exes for me, when my application is opened, it reads some data from MySql database, processes it, then writes the result back to MySql database.
they are very normally useful on servers, but sometimes I get this error, it's not clear when, sometimes after 1 week, sometimes twice a day
Authentication to host '192.168.1.200' for user 'root' using method
'mysql_native_password' failed with message: Reading from the stream
has failed.
this error does not happen on every computer, it does not happen all the time, I never encounter it when compiling on my own computer
I tried a lot of things so far I couldn't come to a conclusion by looking at some suggestions on this site
I added or removed MySql password is not a solution , ports defined to firewall and antiviruses
private string connectionstring = "Server={0};Database={1};port={2};username={3};password={4};CharSet=latin1;SslMode=None";

About action of the open Method(MySQL, Connector/Net)

First of all, I have been started to studying the C# from 6 months ago and I'm not good at English.
So I'm sorry if I say something that you cannot understand.
Now, I'm developing the application with C# that ONLY connect to MySQL server(both of remote and local).
And I use a MySql.Data.Client package, it's version 8.0.12.
This ONLY means "I don't send any queries. I want to find that I can connect to server using a UserName and Password.".
Then, I wrote this code. And I have two questions, and I want to get any advises.
sendCommand = string.Format("host={0}; userid={1}; password={2}; SslMode=none;", pIPAddress.ToString(), mOption1, mOption2);
MySqlConnection mysqlConnention = new MySqlConnection(sendCommand);
mysqlConnention.Open();
if (mysqlConnention.State.ToString() == "Open")
{
result = true;
}
mysqlConnention.Close();
Q1
The application should not send unnecessary packets to server.
However I found it from WireShark and it's "show variable" command.
I tried to change some properties about ConnectionString(in this code, it's called "send Command") because I want not to send "show variable" command. (for example, ChacheServerProperties=true, AllowBatch=false, and so on...)
Can I connect without "show variable" command?
Q2
(It's soloved but I cannot find the causion)
When I started developing this application, I used MySql.Data.Client 8.0.11.
But in that time, the MySqlConnection.Open Method was taken a long time for connection to server.(It was about 7~10 second.)
The network problems was none, and I was able to connect using cmd.exe without a long time.(It was not taken a second.)
I tried any patterns, changed server to connect, restarted OS(both of the application side and server side), changed ConnectionString properties).
MySQL server was not dying and It looked like the cause is not in MySQL server and network.(Getting the application "ServerGreeting" packet from server was no time but next action that the application send "LoginRequest" packet to server was taken a long time.)
However I was not able to slove this problem. But I updeted MySql.Data.Client version to 8.0.12, I can slove!
Is this problem caused by MySql.Data.Client 8.0.11?
And have I any solution?

The application should not send unnecessary packets to server. … Can I connect without "show variable" command?
You can, by using an alternative ADO.NET library: MySqlConnector. It sends a lot fewer packets when opening the connection (but it may not send the absolute minimum possible).
But in that time, the MySqlConnection.Open Method was taken a long time for connection to server.(It was about 7~10 second.) … Is this problem caused by MySql.Data.Client 8.0.11?
This sounds very much like MySQL bug 80030, which is a bug in 8.0.11. That case says it's going to be fixed in 8.0.13, not 8.0.12, but perhaps Oracle changed their release plans after making that comment.
This could also be fixed by using MySqlConnector, which never used an inefficient WMI query that was causing the performance problem in MySql.Data.

ODP.Net OracleConnection.Open cold start very slow

I have a WebAPI service which connects to an Oracle database using Oracle.ManagedDataAccess.dll. Each time after a reset of the application pool (or a deployment) there is a long delay on the first OracleConnection.Open() statement. It's typically around 8 seconds. Subsequent calls are around ~0.5 seconds each.
After reading lots of suggestions regarding server OS and networking issues, i have narrowed it down to the oracle client itself. If I remote debug my code, set a breakpoint on the open statement, and then run Sysinternals Process Monitor i can confirm that the first open statement produces 544 entries, second and subsequent tests produce 2 entries.
The entries are quite random, but mostly relate to Cryptography. A quick overview of the logs:
RegOpenKey, HKLM\SOFTWARE\Microsoft\Cryptography\Defaults\Provider Types\Type 001
RegOpenKey, HKLM\SOFTWARE\Microsoft\Cryptography\Defaults\Provider\Microsoft Strong Cryptographic Provider
RegSetInfoKey, HKLM\SOFTWARE\Microsoft\Bryptography\MachineGuid
These are repeated several times, then there are sections like below:
RegQueryValue, HKLM\System\CurrentControlSet\WinSock2\Parameters\Protocol_Catalog9
RegCreateKey, HKLM\System\CurrentControlSet\Services\Tcpip\Parameters
RegCreateKey, HKLM\System\CurrentControlSet\Services\DnsCache\Parameters
RegOpenKey, HKLM\SOFTWARE\Policies\Microsoft\Windows NT\DNSClient
Then there are several reads of the machine.config file followed by multiple TCP connect and receive to the oracle port 1521. Following this is a section reading the time zone from the registry.
My question is, why is the oracle client doing all of this at first open? Is there any way i can predetermine the answer to some of these questions? (like configure the time zone so it doesn't have to 'ask' Oracle for it)?

Only time I have seen something like this was when the address in the tns connect descriptor was not fully qualified, ie host=computername, instead of host=computername.domain.com.
Issue is likely dns resolution as it goes thru suffixes. I imagine you could put in an ip and eliminate dns altogether as a test. Consider posting your tns entry and connection string as well.
FYI, a lot of things are happening when that first connection is created, ie the pool is established and connections are actually opened vs just fetched from the pool, initial parameters for self-tuning are initialized, etc, so i think number of reg reads is probably a red hearing.

Change CommandTimeout Default Value globally

We migrated some piece of old software to a new server. We used SQL Server 2008 Enterprise in the past and now we are using SQL Server 2014 Enterprise on a new machine, so it should be faster now.
The old software is legacy software and about to expire, therefore I don't want to put much effort in fixing it. But for some reason there is a C# function running a SQL query against the database for which I get the error message
Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding.
All I read about that is, that I have to extend the timeout time by using CommandTimeout. But unfortunately everything runs under "context connection = true". Therefore, it would take quite a bit work to rebuild this function with an opportunity to change the timeout.
And I'm asking myself, why did this run on the old machine and way it won't on the new one. So it has to do something about the new machine or the new SQL Server engine. Is there any way to change the standard timeout of 30 seconds for a command in the .NET Framework or in the SQL Server?
Thanks a lot for any suggestions!

You can set the timeout of a command with the CommandTimeout property:
var cmd = new SqlCommand { CommandTimeout = 60 }

Ok, I didn't find a sollution for the problem, yet, but the timeout is not really the source of the problem. I gained access to the old system and run some tests and it turned out that the same function on the old machine with the old server software runs a lot faster, such that there is no timeout.
Hence, I have to focus on server speed and database tuning.
Thanks to everyone who occupied himself with this question!
Edit:
I found a solution to my problem, indirectly. I couldn't find out, why the execution of the statement on the new machine takes so long. But it turned out that the statement itselft uses table variables. I changed them to a local temporary table in the database tempdb. Now the execution takes less than one second instead of more than 7 minutes!
For me, it looks like a problem with some cache or a miss-configured SQL server. Unfortunately, I'm not really the server administrator and I will not twiddle with it. But I will mention it to the administrators. At least, the program runs now perfectly.

TIBCO EMS connection not resolving in C#

I am working with a program that is meant to publish to and read from an existing TIBCO EMS hosted on a server separate from the program. I have referenced the sample code provided with the TIBCO installation, resulting in a big chunk of the program. Here is the code snippet that I am having troubles with:
1 QueueConnectionFactory factory = new TIBCO.EMS.QueueConnectionFactory(serverUrl);
2 QueueConnection connection = factory.CreateQueueConnection(username,password);
3 QueueSession session = connection.CreateQueueSession(false, Session.AUTO_ACKNOWLEDGE);
When line 1 runs, it goes through alright. When line 2 runs, it goes through alright, however, the connection object is null, resulting in an error during line 3 where a NullReferenceException occurs.
I would have at least expected that line 2 would return some sort of error to show that the request timed out, the credentials were wrong, the url is inaccessible, or at least something to let me know what the issue is, but there is nothing like that, until it hits line 3.
Does it have to do with the configuration of my application? All I have done to get this working is include the TIBCO.EMS.dll as a reference and worked with the code from there.
Could it have something to do with the fact that I am connected to a VPN that requires a proxy? If so, how can I set up that proxy in my code?
Any help would be greatly appreciated. Thank you.

The issue was that I was using the wrong version of the .NET framework to work with the Tibco integration. The version I was using was farther along than the original.

It would think that your server URL is incorrect.
try different urls maybe like tcp://localhost:7222 (where localhost can be the IP/Name of the remote server)
install EMS locally on you workstation and see if you can connect to it. (Default admin with no password)