Jaap Van.Veen wrote in a message to All:

 JVV> As I have recalled earlier, my system (486DX2 66) is much
 JVV> faster with FP40 installed. This has to do with the faster
 JVV> handling of the harddisk. 

 JVV> However during the regular status checks the COM1 port is
 JVV> not serviced in time causing overruns. Does somebody know
 JVV> how I can avoid overrun of COM1. 

 JVV> I am using SIO.SYS instead of COM.SYS since the beginning of
 JVV> my dealing with OS/2.

I run WARP 3 with no fixpaks (other than it is released at FP5.  I upgraded my 
IBM1S506 and the DASD drivers only, and did that at the FB17 level, and that
was needed ONLY for multiple drive recognition on a CD Changer.  Anyway, I
once installed the newer drivers that were released for large drives (>4gigs), 
although my stock drivers recognized my 5 gig drive with no problem, I
installed them just for kicks.  Suddenly, I started getting modem overrun
errors, on the BBS (DOS) and on the internet (OS/2).  I tracked the problem
down to these new drivers, and I'm sure that is exactly where your problem is
coming from.  I tried 9 million things to correct the errors, based on a bunch 
of recommendations in here for switches to the IBM1S506 config.sys line, but
not a damn one worked. I had to put the older disk drivers from FP17 back in
to stop the modem errors.  I was suprised a disk driver could create modem
overrun errors, but it did, absolutly positively was the cause.

I recommend you move that driver to another name, and stick in your old
IBM1s506 driver and see if the problem doesn't disappear.  All you need do is
copy it to the correct directory and reboot.

                                              Jack 
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