ORA-12170: TNS:Connect timeout occurred

When we face "ORA-12170: TNS Connect timeout occurred", then immediately check the following 

• TNS_ADMIN environment variable is defined or not
• ORACLE_HOME environment variable is defined as "C:\oraclexe\app\oracle\product\11.2.0\server". 
• "C:\oraclexe\app\oracle\product\11.2.0\server\Network\Admin\sqlnet.ora" was located NAMES.DIRECTORY_PATH specifies EZCONNECT in the sqlnet.ora file
• EZCONNECT is not the first naming method in NAMES.DIRECTORY_PATH which may conflict with other naming methods specified

Steps need to follow to fix the issue

• Try moving EZCONNECT to the first position in NAMES.DIRECTORY_PATH in the sqlnet.ora file
• Verify that the database server is running
• The following profile parameters may need to be set to larger values in the sqlnet.ora file on the database server: SQLNET.INBOUND_CONNECT_TIMEOUT, SQLNET.SEND_TIMEOUT, and SQLNET.RECV_TIMEOUT
• Try to TNSPing (DESCRIPTION=(ADDRESS=(PORT=<port number> e.g. 1521)(HOST=<IP address> e.g. 10.20.30.40)(PROTOCOL=TCP))) using the TNS Ping button on the toolbar

Consider defining a bean of type in your configuration

A compile-time error thrown by Spring application as following "Consider defining a bean of type 'org.sling.service.ServiceClass' in your configuration". This means we have created a class or interface and trying to use it as a service or bean, but your class or interface doesn't have the feature of bean. 

So, to fix this with a service class use annotation @Service [org.springframework.stereotype.Service] on top of your class declaration will fix this error.

How to push any PDF or word file to Kindle?

Login to Amazon and go to manage your content and device section from your account.

Click on the device tab, after clicking on device tab you will see the below screen. This screen will show you all your kindle apps and at the last your Kindle email address. Using this kindle email address you can push your document to Kindle. For that you have to also set the authorized sender so that email with attachment only with those email address will be get pushed into your Kindle app.

Kindle email address screen

References: 

Amazon Kindle help and support

Send to kindle

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