Facing the following error when testing the connection to MySQL from Replicate:
RetCode: SQL_ERROR SqlState: IM002 NativeError: 0 Message: [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified [122502] ODBC general error.

ans:

Replicate uses 64 Bit ODBC Client to connect to MySql, and the error means that replicate can’t find the ODBC Client.
It can happen if:

1. They don’t have the ODBC client installed (This is for the 64 bit version)-
Run C:\Windows\System32\odbcad32.exe
Check that the driver is listed under the drivers list:
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2. If the user is saying that he/she do have it installed and he/she doesn’t understand how it is not listed – This might be because he/she has the 32bit version of the client.
To check that – The process is the same as in (1) but you should open the 32 bit ODBC Data source Administrator:
C:\Windows\SysWOW64\odbcad32.exe


3. Another explanation is, that they have a different version of The ODBC Driver (Client) than the one we’re looking for– 5.2.
In most cases The ODBC client name is not specifying the Version as a part of the name – MySql is different, and it does specify that – “MySQL ODBC 5.2 Unicode Driver”
To overcome that issue, just specify the exact driver name on Replicate: Managed database > Advanced > Check “Override…” > type “Driver = <ODBC Driver name>
Example:
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https://support.microsoft.com/en-us/kb/942976