Phantom Events

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Andre C
Posts: 23
Joined: Sun Sep 11, 2011 5:00 am
Location: Brisbane, Australia

Phantom Events

Post by Andre C » Sun Sep 11, 2011 10:35 am

Hi Dan

I created a shared calendar that contains many repeating events. It is a seven-day, 20 weeks, rostered-on-duty calendar. Each day contains one repeating events that represents a restored shift. Each event repeats every 20 weeks, indefinitely.

What occurs is that at random for some days show the same event twice. It is the correct event but just showing twice. And when deleting the second event, "the phantom event", the repeating event-chain that is linked to that day's event seems to be corrupted in that the event disappears at some locations (days) where it should appear.

It was not originally so but started to occur after a couple of days of using that particular calendar. The calendar is shared on the LAN only and is used by two contributors and one person as read-only.

It is strange in that I manage to fix-up the calendar and all is OK but after a day or so the problems start to reappear.

On of the computers the calendar is used on is an older, slow laptop with not to much memory. I have a sneaky suspicious that that the calendar gets corrupted, sync-wise, by that slow laptop. But I have no direct proof as the phantom events seem to appears so at random.

Currently, I have the calendar fixed-up again on the origination laptop and I took the slow laptop out of the equation for this calendar, but the calendar is still showing one or two phantom events on another laptop.

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Dan Chartrand
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Re: Phantom Events

Post by VueSoft » Sun Sep 11, 2011 10:31 pm

Hi Andre, thank you for letting me know about the problem. I haven't observed this behavior on my network, but I'm syncing between fairly quick machines. I'll try inserting a slower machine into the mix and will let you know if I'm able to duplicate the problem.
Dan Chartrand, Founder
VueSoft LLC | St. Louis, Missouri, USA

Andre C
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Joined: Sun Sep 11, 2011 5:00 am
Location: Brisbane, Australia

Re: Phantom Events

Post by Andre C » Tue Sep 13, 2011 5:44 am

Update:

It may have nothing to do with a slow computer. It happened again and I now suspect that the VueMinder server gets confused when a user is logged-on concurrently on different computers using the same login name. I checked the date & time on each of these computers and they are all the same time range of less than a minute difference.

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Dan Chartrand
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Re: Phantom Events

Post by VueSoft » Tue Sep 13, 2011 11:06 pm

Hi Andre, thanks for the information. I've tested this condition as well, but haven't been able to duplicate the problem.

VueMinder will attempt to determine the actual time using a NIST internet time server. However, if your computers are behind a firewall or proxy, that might prevent VueMinder from getting an accurate time.

Getting an accurate time is essential for proper syncing. If your computers are up to a minute different in their clock times, and if VueMinder is unable to get the NIST internet time, that might explain some of the intermittent syncing issues you're seeing. Most networks have a way to keep connected computer clocks in sync. I'd check with your network admin to see if this is something you can enable.
Dan Chartrand, Founder
VueSoft LLC | St. Louis, Missouri, USA

Andre C
Posts: 23
Joined: Sun Sep 11, 2011 5:00 am
Location: Brisbane, Australia

Re: Phantom Events

Post by Andre C » Wed Sep 14, 2011 4:36 am

When I said within the time range of less than a minute I was erring on the safe side, on closer inspection it is waiting a few seconds of each other. All computers are time synced with "time.nist.gov". All pings are OK and the time updates run without problems wen I try it manually. No, it is not a time variance issue.

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Dan Chartrand
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Re: Phantom Events

Post by VueSoft » Wed Sep 14, 2011 5:53 pm

Thank you for the information. I'll let you know if I determine what is causing this behavior.
Dan Chartrand, Founder
VueSoft LLC | St. Louis, Missouri, USA

mrbeanpa
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Joined: Sat Oct 22, 2011 10:34 am

Re: Phantom Events

Post by mrbeanpa » Sat Oct 22, 2011 10:48 am

Hi,

Has a solution to this been identified? I've been encountering it for the last few weeks, think it started the version before last. I'm sharing the events between 3 machines using the share over LAN and some events have been duplicated as many as 4 times. I had a cleanup last week and found at least 10 events that had been duplicated at least once. I tried the suggestion of checking all clocks and made sure all were synchronised, initially they were different, but for the past week or more I have checked them regularly and they still appear to be in synch.

I'm not certain but it seems to be after events have had reminders and the reminders have been processed by the user. Also all the events duplicated seem to be recurring events... Other than that I have little indication of the cause.

If it helps the Server is a win7 64 bit machine, this is also one of the 3 'user/client' machines for the calendar, one client is Win XP 32 bit, the other is win7 64 bit.

Many thanks

Phil B

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Dan Chartrand
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Re: Phantom Events

Post by VueSoft » Sun Oct 23, 2011 11:55 pm

Hi Phil, I'm still working on a solution. It's a difficult problem to track down because I'm unable to duplicate this behavior on my network. I believe it's related to a memory caching issue in a 3rd party component that VueMinder uses. I won't get into the gory details, but rest assured I'm working on finding a solution.

If you'd like to help, could you perform a backup of your data (using the Backup Data command on the File menu), and send me a copy, along with a description of which event(s) are showing duplicates? All data will be kept strictly confidential and will be deleted as soon as I've finished with it.
Dan Chartrand, Founder
VueSoft LLC | St. Louis, Missouri, USA

mrbeanpa
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Joined: Sat Oct 22, 2011 10:34 am

Re: Phantom Events

Post by mrbeanpa » Mon Oct 24, 2011 1:33 am

Hi Dan,

Happy to help if I can. Please can you advise where to send the file to, I'm assuming by e-mail?

Phil B

Andre C
Posts: 23
Joined: Sun Sep 11, 2011 5:00 am
Location: Brisbane, Australia

Re: Phantom Events

Post by Andre C » Mon Oct 24, 2011 3:14 am

I don't know if it has anything to do with the duplicated event phenomenon, but:

When I run the he Options -> Sharing -> Cleanup Database function it often states that "50+ previously deleted events have been removed" while I know very well that none or just a few event have been actually removed by me or another user. Running the Options -> Sharing -> Cleanup Database function again will shortly after will usually show the "database already clean" message, but a day or so later it's back to the large number of events removed in spite of the fact that I am sure that no events have been actually removed by anybody.

However, luckily all the events seem to be still there and no events are removed by running that Options -> Sharing -> Cleanup Database function as far as I can ascertain. - Strange...

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