I tried to understand how the Begin...End Transaction works, I wrote a small looping program, what I found is quite a mystery for me.

this is my code:

set multilocks on
tryAgain=0

for nloop=1 to 10

  do while .t.

    select tableA
    replace...
    select tableB
    replace...
    insert into tableC...

    begin transaction

    allOk=.n.
    select tableA
    if tableupdate(.t.)
       select tableB
       if tableupdate(.t.)
          select tableC
          if tableupdate(.t.)
             allOK=.y.
          endif
       endif
    endif

    if allOk
       end transaction
    else
       rollback
       tryAgain=tryAgain+1
       if tryAgain<3
          wait window 'Rollback but try again '+str(tryAgain)
          loop
       endif
       wait window 'Rollback and go next' timeout 5
    endif

  wait window 'pause for 5 seconds, how many loop:'+str(nloop) timeout 5
  exit
  enddo

next nloop

I started the app in 2 PCs, after the third loop, PC #1 got an error:

File is in use by another user.

then Rollback
while it keep looping but always rollback, even the other PC has finished the looping and exit.

PC #1 keep showing:

Rollback but try again 1
Rollback but try again 2
Rollback and go next
pause for 5 seconds, how many loop: 3
Rollback but try again 1
Rollback but try again 2
Rollback and go next
pause for 5 seconds, how many loop: 4

... and so on until the last loop

is there any explanation for this? how to release the lock? what's wrong with my code?

thanks for the help