DSNs are listed in registry key but some of them not showing in the ODBC Administrator

Summary

When you try to create a system dsn, you may not able to see all dsns listed in DSN list. This might be the fact that default value of ODBC DataSources is edited and set to a value different than "value not set" by third party applications. In order to fix this problem :

Solution

Click start->run-> type "regedit"
In registry key go to HKLM\software\odbc\odbc.ini\odbc Data sources registry key
On the right pane if Default registry key entry is different than " value not set" like empty string, or any other value right click on default registry key and click delete
After this operation, close odbc administrator screen and reopen again.
You should be able to see all lists of dsn you have created.

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