Error: "CRC of file [\\path] could not be calculated" appears in the NuGenesis Archive Agent log file - WKB20908

SYMPTOMS

• The following error appears in the SDMS AA activity log file:
  • "PMCRC of file ... could not be calculated" or "AMCRC of file ... could not be calculated"
  • "EMC: FillTransactionDO failure"
• The files named in the error message are not archived by SDMS

ENVIRONMENT

• NuGenesis 9 SDMS
• NuGenesis 8 SDMS

CAUSE

The file or files named in the error messages are exclusively locked by another program.

FIX or WORKAROUND

Check the size of the file. If it is 0 bytes, the Archive Agent cannot calculate a CRC32 checksum for it, and the file is not archived.

If the file is more than 0 bytes in size, it is likely locked by another application. This is a common error message when the Archive Agent reads data files from acquisition machines. It is possible for the Archive Agent to read from a file while it is being written. Most programs will lock files for their exclusive access while writing.  If SDMS happens to open the file for reading during this time, this error occurs. It is not indicative of a problem in itself. Most exclusive locks on files are held for short periods of time, and on the next archive scan, the locked files should be available for archiving by SDMS.

If the error occurs repeatedly—for the same files or for different files—on many archive scans, you should increase the scan interval of the Archive Agent template line, to decrease the likelihood of these errors. It is also possible that a program is holding an exclusive lock for longer than normal, which prevents SDMS from archiving a file, even after multiple runs.  Use the Process Monitor tool from Microsoft on the data source machine to identify any processes that have locks on the files.

ADDITIONAL INFORMATION

This could happen with a UV with Chemstation.

The "PM" part of the "PMCRC ..." message merely refers to time; as in, AM/PM.  The error message template in the code should have a space between the timestamp and the message, but it does not, and thus the time designation AM or PM appears to be part of the error message.