Quote:
Or:

if (%avar == $null) OR (%bvar == $null) { goto end }


You can't use OR in mIRC scripting. || means OR.

Also, although mIRC allows you to not use every parentheses that you should be using, it's not really good coding style to skip them.

Rather than:
Code:
if %a == 1 { echo -a hi }


It's better to use the parentheses:
Code:
if (%a == 1) { echo -a hi }


The same is true for multiple checks as in the example... you should use:
Code:
if ((%avar == $null) || (%bvar == $null)) { goto end }


Instead of:
Code:
if (%avar == $null) || (%bvar == $null) { goto end }


It will work both ways, but it's better coding style to use all appropriate parentheses. It can also make it easier to understand.