Limit (not memory) consumed by Range Names, UDF calls, VB code, st
 

I'm hitting some resource limit in Excel 2007 that seems to be some
combination of:
* The number of Range Names, especially names that refer to EntireRows or
EntireColumns
* The number of UDF calls in cells
* VB code itself
* Run space for the VB code


Error messages when I hit this resource limit (on loading too many
workbooks) include:
* Excel cannot complete this task with available resources
* Out of memory
* Not enough storage
* Excel cannot open the file ... because the file format or extension is
not valid
In many cases, Excel becomes unstable.


In all cases, Task Manager shows Excel at well below its 2gig memory limit;
in some test runs, it was below 600 meg.


My application loads a workbook for each manager in an organization; each
workbook is complex, multi-sheet, large, and carries VB code with commands
and UDFs and needs to run stand-alone. I need to be able to open all the
workbooks simlutaneously due to linked data.

I was able to open more workbooks by any of the following:
* Not enabling macros
* Deleting VBA code
* Deleting Range Names
* Changing Range Names to refer to single cells rather than entire rows or
columns
* Removing UDF calls from cells


Having done all the cleaning I can, I'm now at a point where the above
actions are damaging functionality.

Does anyone have any idea what resource is being consumed?