The subject behavior occurs if you are using a Dell 120T DDS4, or a Dell 122T VS80, attached to an Adaptec 39160 SCSI controller, and Adaptec driver version 6.4.630.100.

To resolve this problem, run ChangerSlow.bat and then restart your server.

The syntax for using ChangerSlow.bat is:

ChangerSlow "Unique Changer Name 1" \["Unique Changer Name 2"\] \["Unique Changer Name 3"\]

Where "Unique Changer Name X" is any portions of the changer name that will cause it to be uniquely found as a sub-key. To determine the value of "Unique Changer Name 1", and optionally "Unique Changer Name 2" and "Unique Changer Name 3", run:

ChangerSlowParams.bat \["Unique Changer Name 1"\] \["Unique Changer Name 2"\] \["Unique Changer Name 3"\]

ChangerSlowParams.bat contains:

@echo off
setlocal
set C1=if NOT \{%1\}<h1><a name="_set_C1_1_set_C1_C1_set_F1_Find_I_C1_set_C2_if_NOT_2_">\{\} set C1=%1
set C1=%C1:"=%
set F1=Find /I "%C1%"
set C2=if NOT \{%2\}</a></h1>\{\} set C2=%2
set C2=%C2:"=%
set F2=Find /I "%C2%"
set C3=if NOT \{%3\}<h1><a name="_set_C3_3_set_C3_C3_set_F3_Find_I_C3_set_Fnd_Find_I_Device_Parameters_MediaChangeNotification_font_size_1_for_f_Tokens_a_in_reg_query_HKLM_SYSTEM_CurrentControlSet_Enum_SCSI_S_F1_F2_F3_Fnd_do_font_echo_a_endlocal_pre_font_size_1_b_ChangerSlow_bat_b_font_contains_pre_echo_off_if_1_">\{\} set C3=%3
set C3=%C3:"=%
set F3=Find /I "%C3%"
set Fnd=Find /I "\Device Parameters\MediaChangeNotification"
<font size="1">for /f "Tokens=*" %%a in ('reg query "HKLM\SYSTEM\CurrentControlSet\Enum\SCSI" /S^|%F1%^|%F2%^|%F3%^|%Fnd%') do (</font>
 @echo "%%a"
)
endlocal
</a></h1>
ChangerSlow.bat contains:
@echo off
if \{%1\}\{\} @echo Syntax: ChangerSlow FindChanger1 \[FindChanger2\] \[FindChanger3\]&goto :EOF
setlocal
for /f "Tokens=*" %%a in ('call ChangerSlowParams %1 %2 %3') do (
 set key=%%a
)
if not defined key @echo No Changer %C1% %C2% %C3% found.&endlocal&goto :EOF
@echo REG ADD %key% /V AlwaysDisableMCN /T REG_DWORD /F /D 1
REG ADD %key% /V AlwaysDisableMCN /T REG_DWORD /F /D 1
endlocal