Many types of anti-virus software can cause problems with DBISAM, specifically with respect to temporary tables created by DBISAM in a temporary files folder on a local drive. The real-time scanning features of som anti-virus applications usually deem any file created with the extension of .dat (the default DBISAM file extension for tables) in the temporary files folder as needing to be scanned and quarantined, and this can cause two errors to occur:


To get around this problem, as of version 4.19 of DBISAM we have included three new TDBISAMEngine component properties for specifying the file extensions for temporary tables created by DBISAM during normal operation:

TableDataTempExtension
TableIndexTempExtension
TableBlobTempExtension

Specifying a file extension other than .dat for the TableDataTempExtension property should solve any issues you may have with anti-virus software. However, be sure to avoid any special executable file extensions such as .exe, .bat, or .com since that will not fix the problem and may make it even worse.

If you are still experiencing issues with these types of errors, then you may need to exclude the DBISAM database directory from real-time scanning by the anti-virus software. Please consult your anti-virus software documentation for more information on how to exclude certain directories from real-time scanning.