Here is the fixed code:

LOCAL lnBuffer_Size, lcBuffer, lcComputerName, lnResult
lnBuffer_Size = 100
lcBuffer = SPACE(0)

DECLARE INTEGER GetComputerName IN kernel32 ;
  STRING @lcBuffer , INTEGER @lnBuffer_Size
lcComputerName = REPLICATE(CHR(0),lnBuffer_Size)
lnResult = GetComputerName(@lcComputerName, lnBuffer_Size)
lcComputerName = LEFT(lcComputerName,AT(CHR(0),lcComputerName)-1)
IF lnResult # 0
  MESSAGEBOX(lcComputerName)
ENDIF

HTH
>Sergey,
>
>I can't get this to work. I get an error that BUFFER_SIZE is not a variable.