PC Adm: Compress Storage Results in Negative Bytes Recovered (103850)

SYMPTOMS

With versions 3.0, 3.0b, and 3.2 of Microsoft Mail for PC Networks, when the Mail administrator recovers disk space by choosing Local-Admin, Storage, Compress, the status may show negative bytes recovered.

CAUSE

This problem occurs because the statistics are based on the free space available on the server, not on the amount of space Mail occupies. The statistics can also be affected by disk usage by other network users. Even if no one else is using the network, the actual space can be affected because during the process of compressing mailbags, copies of existing mailbags and some temporary mailbags (such as COPY.MBG) are created.

RESOLUTION

On a Novell server, the negative number of bytes recovered is usually a multiple of the block size, and varies depending on the number and size of the temporary files created. To avoid skewing the statistics due to the creation of temporary files, the Mail Admin should flag the MBG subdirectory for Purge using the flagdir command, before doing the compression.

As a result, temporary files will be deleted immediately and a more accurate report will be generated. The network administrator can then change or restore the attributes in the MBG subdirectory to the setting prior to the compression.

NOTE: Even with this setting, the statistics will be affected by disk usage of other network users.

If the postoffice is copied to a local drive before the compression is run, this problem does not occur.