well I have this code, at first it was working perfectly....then a little modification just caused an error.
I want to know what are the possible causes of this error

Notice: Undefined index: CSM_blackmere_portside2_1 in C:\xampp\htdocs\PMS\F51-AI_insert.php on line 16

aside from, of course being defined ..
i'm thinking of something like a code might be hindering the variable to get its value ?
e.g. getting the value of an input box but the property Disabled is blocking it

i've been stucked with this, any help would be appreciated...

post your code to see what is at line no.16

Check you code at line ~16 and if you don't find anything strange then paste your script here.

@vibhaJ sorry, I didn't saw your answer! ;D

or maybe you could try to check if there are any missing character like ";" ?
but yeah if it doesn't solve the problem post it here.

thank you guys for the reps, appreciated.