Several things can cause that.
1. Aggregation on memo field.
If the source of this report is a query that performs any grouping in the
memo, it will truncate. You can solve that by choosing First instead of
Group By under your memo field, and then renaming the memo in the report
(since it's now called something like FirstOfMyMemo.)
If there is no GROUP BY clause in the source query, it could be something
else such as a DISTINCTROW.
2. Formatting of memo field.
If there is anything in the Format property of the text on your report, or
the Format property of the field in your table, remove it. For example, the
character causes conversion to upper case, and Access will truncate the
result.
3. See:
Memo Field That Is Exported to RTF Format May Be Truncated
at:
http://support.microsoft.com/default.aspx?scid=kb;en-us;288877
4. See:
When You Export an Access Report the Memo Field Is Truncated
at:
http://support.microsoft.com/default.aspx?scid=kb;en-us;281153
