pgadmin error - sql window

Hi,

I have a persistent PgAdmin problem - when I click the SQL window icon from
the PgAdmin main window, the program freezes and must be force-closed. This
happens without fail, and this behavior has persisted despite reinstalls,
registry wipes, and upgrades. I believe this behavior first occurred after
trying to process to parse a wikipedia dump file with a massive (~100 Mb)
query. I can still execute queries using the psql console window, but as I'm
fairly new to full-blown sql (coming from Access) this really slows down the
development process. Currently I am using PgAdminIII 1.12.2. This issue is
limited to my work desktop computer (Dell T1500 quadcore with Windows 7
32-bit), which does have a centrally managed Symantec Endpoint antivirus
installed. My personal netbook is running the same version of PgAdminIII
without issue.

I'd really appreciate any help you can offer, and would be happy to supply
additional info if needed.

Thanks in advance,
Chris