For some reason, the base station can not complete the process of transferring the logged data of the individual loggers. Often, one (or more) loggers have an issue. You are able to identify which logger is causing the issues. A red square is drawn around the relevant logger. Separately, when clicking that logger, it show: Logger data file(s) incomplete or missing.

CAUSES

1. The logged duration exceeds the specified limit of 16 days. If the data loggers store too much data, it can cause the logfile to be corrupt.
2. One of the loggers contains incorrect / corrupt data.
   1. Because of incorrectly mounting the loggers, the measured data is corrupted.
3. One of the loggers never started logging. Resulting in empty logger files.
   1. During the B2L step the logger has been armed.
   2. Right after, the battery "low" warning is displayed on the Base station (BS).
   3. The batteries of the respective logger are replaced.
   4. Because of this, the logger forgets everything (including that it had been armed)
   5. However, the BS think it has successfully armed the logger, and doesn't indicate to re-arm the logger.
   6. Because of this, and audit can be started, with a logger that is not logging.
4. Some firewalls can detect the messaging between the base station and the cloud  as a threat. Because of this, the transfer is corrupted.

Question: If I replace batteries in a logger AFTER it has been "armed" and is currently logging... Will it erase the audit currently stored in it, or will it be good to go after battery replacement?

Answer: The logger will basically forget everything that it was told, and has already logged. The logger will no longer know that it was instructed to log something, nor what it was instructed to log. If you were to replace the batteries after the logging period is completed, but before you sent the data to the base station, it will also forget all the logged data. The audit will be erased. Do not change the batteries during this period.

1. Try running the B2C step from a different location using a different network.
   1. Try uploading the data using the USB feature.
      1. Verify if your base station supports the USB-feature
         1. http://support.air-insite.com/en/support/solutions/articles/33000204508-how-to-identify-whether-my-base-station-supports-usb-download-upload-
      2. If it does, consult the following article to learn how to use it: http://support.air-insite.com/en/support/solutions/articles/33000204527-how-to-use-usb-option-of-base-station-v2
      3. If you follow the entire article, you will start a complete new audit, causing you to overwrite all existing data. Of course this is not desires since we want to maintain the data that has already been logged. Therefore you can find some extra guidelines, specific for this issue below:
         1. You shouldn't need to create a new audit but you will still need to download the config.bin file to your base station and perform a few of the steps before the B2C step will work. You should have success if you do the following from the article:
         2. Complete steps 2, 3 and 4.
         3. SKIP step 5 - this is important! If you redo the B2L step it overwrite the data saved on the loggers.
         4. Ignore steps 6 and 7
         5. Complete steps 8 through 12
2. If this wouldn't work for any reason then at this point you can try setting up a new, identical audit using the same loggers and base station. Follow the same steps above and be sure to skip the B2L step! This is a more "surefire" approach, but shouldn't be necessary if you're able to do the above steps for the original audit.
3. If all of the above has not helped you to resolve this issue. Please redo the complete audit, and repeat the logging period.