dim twain as TwainMBS // your twain object
dim devices() as TwainIdentityMBS = twain.AllDevices
dim found as Boolean
dim NameToFind as string = "MyScanner123"

for each device as TwainIdentityMBS in devices
  
  if device.ProductName = NameToFind then
    found = true
    
    // lets use this one
    twain.SelectDS(device)
    
    if twain.Lasterror <> 0 then
      MsgBox "Failed to select "+device.ProductName
    else
      'MsgBox "OK"
      exit
    end if
  end if
next

if not found then
  MsgBox "No scanner found named: "+NameToFind
end if

dim t as TwainMBS // your twain object

// check supported sizes

const ICAP_SUPPORTEDSIZES = &h1122
dim type5 as Integer
dim EnumCount as Integer = 0
dim EnumItemType as Integer = 0
dim EnumCurrentIndex as Integer = 0
dim EnumDefaultIndex as Integer = 0
dim EnumValues() as Integer = t.GetEnumerationCapability(ICAP_SUPPORTEDSIZES, EnumItemType, EnumCount, EnumCurrentIndex, EnumDefaultIndex)
dim e5 as Integer = t.Lasterror
dim c5 as Integer = t.ConditionCode

dim t as TwainMBS // your twain object

t.OpenDS

if t.Lasterror <> 0 then
  MsgBox "Failed to open device: "+str(t.Lasterror)
  Return
end if

const CAP_FEEDERENABLED = &h1002
const CAP_FEEDERLOADED  = &h1003
const TWRC_FAILURE = 1
const TWCC_CAPUNSUPPORTED = 13

// query before
dim type1 as Integer
dim n1 as Integer = t.GetIntegerCapability(CAP_FEEDERENABLED, type1)
dim e1 as Integer = t.Lasterror
dim c1 as Integer = t.ConditionCode

// set on
t.SetBoolCapability CAP_FEEDERENABLED, true
dim e2 as Integer = t.Lasterror
dim c2 as Integer = t.ConditionCode

// query after
dim type3 as Integer
dim n3 as Integer = t.GetIntegerCapability(CAP_FEEDERENABLED, type3)
dim e3 as Integer = t.Lasterror
dim c3 as Integer = t.ConditionCode

// now query loaded?
dim type4 as Integer
dim n4 as Integer = t.GetIntegerCapability(CAP_FEEDERLOADED, type4)
dim e4 as Integer = t.Lasterror
dim c4 as Integer = t.ConditionCode

if e4 = TWRC_FAILURE AND c4 = TWCC_CAPUNSUPPORTED then
  // not supported!
  Break
end if

dim twain as TwainMBS // your twain object
dim devices() as TwainIdentityMBS = twain.AllDevices
dim found as Boolean
dim NameToFind as string = "MyScanner123"

for each device as TwainIdentityMBS in devices
  
  if device.ProductName = NameToFind then
    found = true
    
    // lets use this one
    twain.SelectDS(device)
    
    if twain.Lasterror <> 0 then
      MsgBox "Failed to select "+device.ProductName
    else
      'MsgBox "OK"
      exit
    end if
  end if
next

if not found then
  MsgBox "No scanner found named: "+NameToFind
end if

dim t as TwainMBS // your twain object

t.OpenDS

if t.Lasterror <> 0 then
  MsgBox "Failed to open device: "+str(t.Lasterror)
  Return
end if

const CAP_FEEDERENABLED = &h1002
const CAP_FEEDERLOADED  = &h1003
const TWRC_FAILURE = 1
const TWCC_CAPUNSUPPORTED = 13

// query before
dim type1 as Integer
dim n1 as Integer = t.GetIntegerCapability(CAP_FEEDERENABLED, type1)
dim e1 as Integer = t.Lasterror
dim c1 as Integer = t.ConditionCode

// set on
t.SetBoolCapability CAP_FEEDERENABLED, true
dim e2 as Integer = t.Lasterror
dim c2 as Integer = t.ConditionCode

// query after
dim type3 as Integer
dim n3 as Integer = t.GetIntegerCapability(CAP_FEEDERENABLED, type3)
dim e3 as Integer = t.Lasterror
dim c3 as Integer = t.ConditionCode

// now query loaded?
dim type4 as Integer
dim n4 as Integer = t.GetIntegerCapability(CAP_FEEDERLOADED, type4)
dim e4 as Integer = t.Lasterror
dim c4 as Integer = t.ConditionCode

if e4 = TWRC_FAILURE AND c4 = TWCC_CAPUNSUPPORTED then
  // not supported!
  Break
end if