'cant open any more databases' error?

[dd_bdlm]

I have recently updated my database to include a postcode recognition
function. And to perform calculations based on that recognised value.
The query that makes all these calculations is very large and takes a
good while to run (up to a minute?). (But I need all this data in one
query so it can be reported in one report.). My problem now is I enter
my client details screen and then click to go through to their records
(which involves running the big query) then when I click on the report
I get 'cant open anymore databases' error. Is the system just out of
memory from running such a big query? Is there anyway I can split the
query and have several smaller queries and then join all the results
together in a big query. Will that help or exacerbated matters (ie
making it more complex - note I was previously also getting errors
saying 'query is too complex' but managed to resolve those). Arrgghhh
this is so frustrating as I am so close to the end of a major update.
Please help!