The maximum size of a Jet (MDB) database is 2GB, so at 50 MB per month,
you'd exceed that in about 40 months. If 50 MB is the size of the text file,
that may translate to rather more than 50 MB of Jet data. Try compacting the
MDB, making a note of the size, then importing, then compacting, then
comparing the new size to the old size, to estimate how much the MDB will
grow with each import.
Unless this will be a short-term project with a small number of users, I
think you probably need to be looking at a heavy-duty database engine such
as SQL Server. (Not MSDE, which has the same 2GB limit as Jet).

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Brendan Reynolds (MVP)
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> Hi All,
> I have a question regarding the capabilities of Access and I would
[quoted text clipped - 10 lines]
> Thanks in advance
> Frank