I am running plsqldeveloper on a windows xp virtual machine. (Created on a windows 7 box). When I start plsql developer on the virtual xp machine I type in a vallid Username/Password there are no Databases in the drop down list so I type in a valid database name then I get the following error: Sql*Net not properly installed OracleHomeKey: OracleHomeDir:. It appears to me that plsql developer cannot find the tnsnames.ora. It is this folder: C:oracleproduct10.2.0Client_2NETWORKADMIN folder along with sqlnet.ora. I don't know what is wrong. Should tnsnames.ora and sqlnet.ora be placed in another folder? Please help with this urgent issue.