I can think of an alternative, if it makes sense to you: partition the
Excel table vertically (maybe into thirds) and populate it in steps.
You could fill 1/3 of the Excel table with each of 3 Queries, and the
final result will look just as good as if you'd done it in one step.
You might be able to put the 3 Queries into a Macro to simplify running
them in the proper order.  Or you could have the Excel cells reference
the proper parts of more than one Access Query.  My guess is that the
S.I.H.P. doesn't care about the internal structure of either the Excel
spreadsheet or the Access Tables, but rather that the results look good.

(BTW, Excel has a similar limit -- no more than 256 columns in a row.)

You might check out the topic "Microsoft Access database query
specifications" in Access Help, but it won't be very comforting if you
find that you really can't use as many fields as you need.  But if you
really do want to know what the maximum is, you could (in a junk COPY of
your database, not the working version) try reducing the number of
fields little by little until you have a set that works.  Or you could
do a binary search: Does it work with 128 fields?  Does it work with 128
+ 64 = 192 fields?  (Etc.) But even if you find the exact answer, it
probably won't make you much happier.

  -- Vincent Johns <vjohns@alumni.caltech.edu>
  Please feel free to quote anything I say here.

Anton,

I am not sure whether these comments are relevant.  I recently had a
table where Access wouldn't let me add any new fields, even though the
number of fields already in the table was less than 250.  Compacting the
database did not resolve this.  But I created a new .mdb and imported
all objects from the existing one, and after that the problem disappeared.