Investigator will check for the following conditions which it considers to be bad data conditions:
The open is higher than the high.
The open is lower than the low.
The close is higher than the high.
The close is lower than the low.
The high is less than or equal to zero.
The low is less than or equal to zero.
The close is less than or equal to zero.
The volume is less than zero.
Investigator will also inform you of bad dates in your files, such as if a date is a Saturday or Sunday, but this will not exclude the file from historical testing.
If you checked the Find Files with Bad Data dialog box option asking you if you want Investigator to flag files that it cannot open due to insufficient data, Investigator will flag the files that have less than ten dates in it or files that it can not read due to corruption.