DX Keeper uploads by selecting LOTW and then doing an "Add
Requested". The Add Requested only selects those QSOs which do not
have "R" in the LotW sent box (meaning QSL requested). Once the "R"
is there DXK will not unload the QSO again. The next step is
to "Sync LotW QSOs". This button requests LotW to download a file
with the QSOs that were recently uploaded. DXK marks the log with
LotW Sent = "Y" and Lotw Rcvd = "R". This is insuring that there is
a LotW record matching your log. Then periodically you check for
QSLs with the "Synch QSLs" button. This downloads any QSLs (matched
records) and marks your log with LotW Rcvd = "Y".
Manually log into LotW and check to see if you have really uploaded
duplicate entries. If you have please get on the DX Lab yahoo group
and ask Dave for help. DXK is designed NOT to do duplicate uploads.
It is extremely unlikely that your DXK upload is "crashing" LotW.
There are periodic maintenance intervals where LotW goes offline.
There also intervals (primarily after contests) where LotW seems
broken. If there is a problem with LotW, DXK should report an error
message to you. So if you still think there is a problem, please get
on the DX lab yahoo group and ask.
Regards Ed KE3D (very happy DXK user and fairly happy LotW User)