VB App Puzzler!

[cstrong]

Hey,

Hope you all got your thinking caps on! This one has me stumped!!

We have a freight application that prints out UPS labels. If you send only one or two boxes (1 or 2 labels) it is fine. If you send three boxes (3 labels) you get four labels. The label number (1 of 3, 2 of 3 etc) goes all mad...we get 1 of 3 three times and 3 of 3 once and all the tracking numbers are crazy!

We move the machine from the warehouse to my desk and run the application and it works fine! Move it back down to the warehouse and it does not work. This is on a Win2k machine. The same happens on an XP box. On NT4 it works!

Normally, I'd assume it was an issue with Win2k or XP but as I said, when the machine was sat upon my desk, it worked without fault..!

We have tried the application logins as well as my login (to sql server).

We thought it could be the network, but we plugged the patch lead into the NT4 box and that was fine!!

Well....Any idea's....at all...??????

Thanks in advance!
Clive

 

[Norris68]

How are you printing?
Direct to Printer object?
DataReport?
API?
Other?

 

[CajunCenturion]

First thing I would do is make a chart with Location and Operating System, and from what you've said, the chart looks like the following (always using the same printer):

OpSys Location Results
----- -------- -------
Win2K Desk Pass
Win2K WareH Fail
WinNT4 Desk Pass
WinNT4 WareH Pass
WinXP Desk Pass
WinXP WareH Fail

From this chart - you can elimate individually the Application, the Operating System, and your desk.

So what is different about printing on from your desk, and printing in the warehouse (that does have an OS component).

Could be:
-The length and/or quality of the printer cable
-Differences in Print Drivers between the Machine on your desk and the Machine in the Warehouse
-Environmental Considerations in the Warehouse (heat, cold, etc)
-EM Interferance in the Warehouse, or along the cabling to the print location Good Luck
--------------
As a circle of light increases so does the circumference of darkness around it. - Albert Einstein

 

[cstrong]

Hey,

Were using API calls. OpenPrinter, WritePrinter, etc using the winspool.drv library.

Clive

 

[Norris68]

What printers & drivers are you using?

CajunCenturions comments are sensible.

I once had a machine doing strange things - I finally narrowed it down to the ring main cable that ran round the factory picking up radio interference from the taxi firm next door!

Possibly your mains supply is not very clean. Are any other applications/machines affected in the warehouse?

 

[cstrong]

Hey,

Thanks for your help on this! We fixed it. It turned out that the printer port flow control was set to "None". We changed this to "Hardware" and all was fine!

Clive