After upgrading the TIBCO Data Virtualization Server, the user can face an error as below after executing the 'backup_export.bat' file.
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An internal error has occurred. java.o.IOException: Check if the system for encryption settings are writable and try again
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Steps to resolve this issue are mentioned below:
Step 1: Navigate to server_values.xml file in <TDV_INSTALL_DIR>\conf\server\.
Step 2: Copy the encrypted password from server_values.xml file.
Step 3: Open init_server_keystore_files.bat located at <TDV_INSTALL_DIR>\bin\init_server_keystore_files.
Step 4: Set Encrypted KEYSTORE_PASSWORD in init_server_keystore_files.bat which was copied from the server_values.xml

For example in the server_values file the encrypted password are present as:

<common:attribute>
    <common:name>/server/communications/keystorePassword</common:name>
    <common:type>PASSWORD_STRING</common:type>
   <common:value>Encrypted:ENC(xVvz+t2pTY/O+XrI521pig==$DNOYrlPHqK6YLB05FlwuUA==)</common:value>
</common:attribute>

The password that has been saved to the server_values.xml file, simply copy that in init_server_keystore_files.bat
==> set KEYSTORE_PASSWORD= ENC(xVvz+t2pTY/O+XrI521pig==$DNOYrlPHqK6YLB05FlwuUA==)

NOTE: By setting the encryption password in init_server_keystore_files the same as that is present in the server_values.xml file will help the user to execute the backup_export.bat.