Hi vlad,

>Following are my thoughts, but I don;t know if they help...

>Think, can something external to VFP switch current workarea? No.

Actually this is not entirely true. External components like ActiveX can have any influence on how VFP code is ran. Fact of the matter is that on the form where this problem is arising, I use a hflexgrid. which in fact has some VFP code attached. Many ActiveX controls are depended off sevaral DLLs supplied by windows.

Also we know that certain printerdrivers cause problems in VFP. As I don't know much about the internals of VFP, how can I be sure that there are circustances which can lead to the described situation.

However, you've provided me with one possible cause though: I'll investigate if this ActiveX control has something to with it and if this can be solve with Autoyield.

>One is that some code running between lines execution and cause code running and switching current workarea. It is possible only in certain cases. AutoYied setting prevents any of such code execution. When it allows events processing between lines, only 'ON' definitions could run code between lines, such as ON SHUTDOWN, ON KEY LABEL etc.

I don't use ON KEY LABEL, and I doubt that ON SHUTDOWN has something to do with it.

>Just check in your application all such code for subject of the workarea change. It is also a good practice to remember current workarea and restore it after work. I do this very suspiciosly any time I see routine might be used by generic way.

I use the same strategy, and i'm very strict in that, however between the select and the test for the field are no function calls, only VFP statments like SCAN, SEEK(), etc.

>Second is quite funny. I met it in my VFP framework year ago. When I receive error, I see workarea is different, causing me to think that something changed workarea. However, after some strict investigation, I figured out that problem was completely onother. Current workarea was just changed by error handler! So, check it out carefully, when you receive error, workarea might be changed by error handler causing you're mistaken.

In my case it seems not to be the case as these errors are registered by the global error handler, any other problem (which are not occurring) should be regitered also.

After getting more details about the problem. It seemed to occur on one out of 5 machines only. The machine is a W95, 32 MB IE 4.0 machine.

>Also, I have a question: do you use data sessions switching often?

datasession switching ? Mannually ? No !
OTOH, my toolbar is refreshing its contents each second and the toolbars datasession is another than the executing form.


Thanks,

Walter,