Error Running BOM Cost Report

Occasionally when running the BOM Cost Report we get the error below.
There is no MfgSysData directory under c:\epicor but the report runs
normally for other parts. I tried it on several computers and always
get the same error. Immediately after I can run the same report for
another part and it works fine. We also tried removing all materials
and operations from the part and re-entering them but no luck.

Could not find a part of the path "c:\epicor\MfgSysData\Reports\Mark
T\BOM Cost Report76347.TXT".