Int 15 Fn 12  - Desqview V2.50+ - Send Message 00h With Error Recovery     [Q]

   AH = 12h
   BH = 80h

Note:  this function is identical to AH=12h/BH=00h, except that DESQview will
     not pop up a "Programming Error" window, instead returning an error
     code in AL (see #0381)

See Also: AH=12h/BH=00h

(Table 0381)
Values for DESQview error code:
 00h   no error
 01h   invalid values
 02h   alias invalid
 03h   handle valid but wrong type
 04h   invalid handle