Deleting lines from the volhist file doesn't do anything.
The volhistory information is still in the data base.

Here is an old post from ADSM-L from "dave", it worked for me:
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In TSM versions prior to 3.7.4 and 4.1.3 there was a bug concerning deletion
or expiry of backupsets. This bug is solved in the newer versions, that is,
delete works as it should (removes entry from volhist). The expire however,
still does not work 'as designed' : the volumes still remain in the volhist,
even after the backupset has expired and dissappeared. To get those volume
out of the volhist (evt. make them repappear as scratch volumes) you have to
use the following (undocumented !) command:
delete volhist TOD=today vol=<volumename> TYPE=backupset force=yes

The parameters vol=, type=backupset and force=yes are new in 4.1.3, and are
not described in the help (h del volhist) or anywhere else.

I haven't tested it on 3.7.4 yes, but it seems to work on 4.1.3.

I'm fairly certain this will be of great help to some people on this list,
it sure was for me...
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