>>You may try using the TRY / CATCH.
>>
>>

>>var oH = 0;
>>try {
>>     if (LevelExteremaListHeight)
>>     {
>>         oH = LevelExteremaListHeight
>>     }
>>CATCH {
>>     oH = <somedefault value or don't change>
>>}
>>

>>
>>I thought there was a function similar to VARTYPE, but I may be thinking of VBscript.
>>
>>I use too many languages.
>
>Thanks
>
>I had to adjust to:
>
>

>     if (window.LevelExtremeListHeight)
>     {
>         oH = window.LevelExtremeListHeight
>     }
>

>
>to make it work.

glad you found your solution.