problems with navision flickers

mhansen

hi.

I have a little problem with Navision 5.01.
We have some computers that logs on to Navision with a local client installed which then join the navision server on the network.
But we have in the past 2 months experienced the screen flickers in Navision and if the users are typing something in there navision session they lose that data.

have heard of that problem before?
how do we solve it?

The computers and server located on the same switch in the network.

kriki

The screen flickering seems to me more a problem of citrix than of local client.

About losing typing something that is lost seems more like that the session is writing something to the DB but has to wait because the database/records are locked by another session. After the locking has finished, NAV frees itself again but all the chars you typed in the same time are lost.

Do you have SQL or native? (with native server the problem of locking can be worse than with SQL server because native server only know tablelocks).

PeterD

We have something similar on a couple of computers which don't connect to a Terminal / Citrix server. I didn't fix it yet.

My observation:
The user is entering data into Navision.
Navision flickers (because focus is shifted shortly to some other program and back to Navision?)
When Navision gets focus again the entire field gets selected.
The user is still typing which in turn overwrites all selected text.

@mhansen: Is your observation the same?


(Technical 5.0 SP1 Native)

Alex_Chow

Are there any code to update the screen on the timer trigger?

Savatage

We had a form like that using the OnTimer trigger. It was so annoying we got rid of it. You had to wait for a flicker then type as fast as you can before the next filcker screwed up what you were typing. Don't know if that's what's happening here but the desciption of what's happening sounds similar.

kine

One our customer reported same thing, but I never saw it on my own and I was not able to "guess" what is the problem just based on the description... but again, it was problem of locally running client, not citrix/rdp.

mhansen

hi.

Well the user does have to type anything just when they are in a local installed navision and are doing nothing it flickers.
And if they are typing something and the flickering comes they lose what they have typed.

can it be something with the database???

thank you all for your help.

kine

For me it looks like some external program gaining temporarily focus outside NAV or something like that... or as it was written, something running in the timer in NAV changing the focus for short time...

kriki

kine wrote:

something running in the timer in NAV changing the focus for short time...

Or doing a CurrForm.UPDATE....

Alex_Chow

I put my money on Currform.UPDATE.

mhansen

Hi again.

I have just tried to make one user only open Navision but it is the same problem.
So it is not another program that makes the problem.

that curr.form update what can i do to check if is the problem???

kriki

Check if in the "Form - OnTimer()"-trigger, there is a CurrForm.UPDATE statement. Or a function call in which that statement occurs.

PeterD

I'am pretty sure it isn't a OnTimer in our case. I don't think it's an Update either on that form. But I will check both.

mhansen wrote:

...
I have just tried to make one user only open Navision but it is the same problem.
So it is not another program that makes the problem.
...

It still can be some Windows process that is causing this.

PeterD

Our user that experiences the Navision flickering on a daily basis just occasionally uses a form with an OnTimer event in it. This is most likely not the source of his problem.

He uses several forms with CurrForm.UPDATE in it. But that UPDATE is triggered by an action of himself (like OnValidate, OnPush, OnAssistEdit). Because the flickering also occurs when he is not actively using Navision this probably isn’t the source either.

Another 2 forms use XML DOM messages to update subforms from other subforms. The messages are sent as a result of a user action. But I don’t exactly know how these sent messages result in triggering Navision. Is it possible for other (Windows) processes to trigger Navision?

kriki

Try with the debugger or with the client monitor to see what code is triggered all the time (if any code is triggered). Maybe this way you can find out what is causing the flickering.

PeterD

We don't control the moment the flickering occurs so it will be hard to use the debugger for this.

I set the client monitor for our user so I hope to get some data the next couple of days.

kriki

You mean they don't have it all the time?

PeterD

Correct.

With this user it happens a couple of times a day. The screen flickers about 6 times before he is able to continue to work. But the exact time isn't predictable.

PeterD

I had my user set the Client Monitor for a couple of days and was informed when the screen flickered. I studied the results with my new extended client monitor. (Thanks MBerger!)

The OnTimer trigger never fired.

CurrForm.UPDATE was executed several times, but always more than 1 minute before the flickering occurred. Since the flickering itself only costs a couple of seconds I also ruled this out as the source.

I guess this is a dead end.


Our newest test is connecting the switch the user is on to an UPS. But if you have other ideas, please let me know. Thanks.

mhansen

Hello again.
We found the error and it was in the GPO the fault lay.
It was refresh rate which stood at 5 min and when we change it to only update once then it worked without the flicker.

Thanks for the Help guys.

Excepti0nal

Were you saying that you updated the GPO refresh interval with users? Also did you update it on the client or the domain controller?

thaug

I've seen this problem occasionally on clients as well. It is very variable. In these cases, I've heard from users that they have lost data after it finished flickering. Never been able to diagnose it since it happens so infrequently and without notice.

The only thing that I've been able to associate it with was when .NET updates were being applied to a client in the background. After a .NET update is applied, the .NET Runtime Optimizer runs and does some work at a slow pace as to not interfere with normal work. Since NAV uses some .NET components, this is a possible thing to look for.

mhansen, what GPO are you talking about?