500 Internal Server Error

Technical details:
Error: access to uninitialised variable - (array element 0)
***  in function "MI_is_obj_available"
***  line: if (({L2}[0]) = "archive") then...endif
***  call: MI_is_obj_available ("O58535")
***  call: MI_mkurl_object ("O58535")
***  call: MI_get_object_field_display ([ix_recmon_record], 1)