What causes BASEXTERR?

a complex BASIC system I’m working on is crashing out with
19:41:18.98 * Error *
Error : &80000002
Message: Internal error: abort on data transfer at &FC199788
19:41:18.98 * BasExtErr * ERR=&80000002 &FC199788 Internal error: abort on data transfer at &FC199788

• Error ** ERR=&80000002 Internal error: abort on data transfer at &FC199788 in “Libraries.winmenulib” ERL=-2
  Memory: Prog=53,886 Vars=919,260 Free=3,118,956 Stack=56 Undefined=0 Slot=4000K

I’m guessing something is overwriting part of the stack, but I wondered whether there was any way to narrow the problem down.

Rearranging the sequence of function calls alters the line shown, and in many cases the line is a LOCAL statement.

The section of code preceeding the problem is manipulating a window, creating icons and allocating text buffers to them. However all my checks seem to show that the buffers are within the DIMmed block. changing the block size has no effect on the error.

The BasExtErr line is probably just the first error repeated, and is from the beta version of Reporter that you are running … and that may be involved in the aborts. I will reply to your PM about your problems as soon as I can. I am not sure why you should think the stack has been overwritten – a length of 56 would be normal if within a proc with no parms.