check if a registry key exists with WScript

Question

im trying to check if a registry key exists and no matter what i try i always get the error message "unable to open registry key for reading"

the code im using:

keyPath = "HKEY_LOCAL_MACHINE\\SOFTWARE\\BOS\\BOSaNOVA TCP/IP\\Set 1\\Cfg\\Sign On\\";

try
{
    var shell = new ActiveXObject("WScript.Shell");
    var regValue = shell.RegRead(keyPath);

    shell = null;
}
catch(err)
{

}

what im missing here?

Answer 1

you are trying to open HKLM hive and probably WScript (or user you start it) have no permissions for that
you can look on permissions with regedt32

Answer 2

You probably need to remove the trailing slash. If you use that, if will look for the default value for the key you have specified, and if it does not find it, will give that error.

Conversely, if you try to access a key as if it was a value by using no trailing slash, you will get the same error.

Some examples trying to access a key:

Fails:

var keyPath = "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion";
var shell = new ActiveXObject("WScript.Shell");
var regValue = shell.RegRead(keyPath);
WScript.Echo("Value: " + regValue);

Succeeds (but gives empty result since Default value is empty):

var keyPath = "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\";
var shell = new ActiveXObject("WScript.Shell");
var regValue = shell.RegRead(keyPath);
WScript.Echo("Value: " + regValue);

Some examples trying to access a value:

Succeeds (output is Value: C:\Program Files):

var keyPath = "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\ProgramFilesDir";
var shell = new ActiveXObject("WScript.Shell");
var regValue = shell.RegRead(keyPath);
WScript.Echo("Value: " + regValue);

Fails (shouldn't use trailing slash when accessing a value):

var keyPath = "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\ProgramFilesDir\\";
var shell = new ActiveXObject("WScript.Shell");
var regValue = shell.RegRead(keyPath);
WScript.Echo("Value: " + regValue);

Answer 3

i am also getting the same type of error for reading the default printer in javascript:

I am using the below statement to read the registry for default printer.

var sDefault = "" var oShell = new ActiveXObject("wscript.Shell"); var sRegVal = 'HKCU\Software\Microsoft\Windows NT\CurrentVersion\Windows\Device'

 sDefault = oShell.RegRead(sRegVal)

GetDefaultPrinter = sDefault What would regRead return in case it does not find the registry, I am not able to trap that, instead I am getting a javascript error like unable to read registry key ''HKCU\Software\Microsoft\Windows NT\CurrentVersion\Windows\Device'