LC fails to start

[CAsba]

Hi all,
Yesterday I worked on my project, and shut down in the normal way. Later I tried to run it again, but it did not start. In the start centre the whirly icon showed for less than a second then disappeared and nothing happened, having selected firstly, the C: file, then the E: file. Since then I have spent hours trying to troubleshoot the problem, including re-installing, downloading afresh and re-installing, trying with previous copies (changing their names to appear to be 'current' copies (that previously ran without a problem)), and repeating all the above on a different computer. This has occurred on the date of my second monthly payment - I changed from the standard plan to a monthly plan just over a month ago - and it occurs to me (of course I may be wrong - I'm totally in the dark) that LC is not flagging the new licence on start-up.
Anyone any ideas ?

[Klaus]

Hi CAsba,

you could try to delete your LC preferences file and then try again.
Don't know where this file is located on Windows, search for a file named: livecode7.rev and delete it.
Then try to start LC again and tell us if that worked.

Best

Klaus

[dunbarx]

CAsba.

If that does not work, contact LiveCode support while there is still daylight over there, to see if your other theory is correct.

support.livecode.com

Craig

[CAsba]

Hi Klaus,
Yes, I did that but it made no difference.
Thanks anyway.

[Klaus]

Sometimes restarting your computer helps...

[jacque]

When you reinstall or update LC it asks which license you want to use. Several of us, including me, didn't realize that there's a button that allows you to scroll through your available licenses. It may be that you chose the wrong one. Try reinstalling and look for the button (I think it's an arrow?) that allows you to pick the correct license.

[CAsba]

Hi Klaus, yes I tried resarting the computer - no luck.

Hi Jacque, I just downloaded and installed afresh - I didn't see any options for licences. and..no luck.

Hi Craig, I'm in touch with Panos about it.

Thank you all for your concern and suggestions.

[CAsba]

Hi Jacque,
I didn't see the button. I've been in touch with LC via chat - evidently if it was a licence issue I wouldn't have been able to proceed as far as I did. Thanks anyway.

[CAsba]

Hi all,
I ran a 3-day old copy stack and it runs, and after I shut it down it runs again. So I've got past the problem of not being able to run LC, but at a cost of two days work. At that time - 2 days ago - I encountered another problem, that a datagrid was not showing its data, and the vertical slider was not showing (all the data was still there in the Contents). Now I can't recall how I got the data to show, but somehow I did, and duplicated the DG incase it happened again in future, thinking if the data is a no show in one dg, maybe not in the other, I can just copy it ?!?! . I think it may be something around this issue that caused the later not-able-to-run issue. I've also noticed that after each shutdown of LC lately, the remaining computer disk space goes down dramatically - in gigabytes !
Do these symptoms ring any bells, anyone ?
Oh, and one more thing, I've noticed a red dot in the PB alongside a button - what's it mean ?

[stam]

Hi all,
I ran a 3-day old copy stack and it runs, and after I shut it down it runs again. So I've got past the problem of not being able to run LC, but at a cost of two days work. At that time - 2 days ago - I encountered another problem, that a datagrid was not showing its data, and the vertical slider was not showing (all the data was still there in the Contents). Now I can't recall how I got the data to show, but somehow I did, and duplicated the DG incase it happened again in future, thinking if the data is a no show in one dg, maybe not in the other, I can just copy it ?!?! . I think it may be something around this issue that caused the later not-able-to-run issue. I've also noticed that after each shutdown of LC lately, the remaining computer disk space goes down dramatically - in gigabytes !
Do these symptoms ring any bells, anyone ?
Oh, and one more thing, I've noticed a red dot in the PB alongside a button - what's it mean ?

Hi CAsba - just checking:
When you say 'fail to start' do you mean:
1. Launching by opening a stack crashes LC immediately? or
2. You launch the app without opening as stack and it crashes immediately?
Or something else?

I recently had issue (1) and had to start LC without opening a stack and had to 'Suppress Messages' so I could open the offending stack and fix the issue, otherwise it would crash immediately (a recursion problem - happily fixed).

On a related note, be aware that the datagrid is a group masquerading as a widget - as such it's various components can become untangled and it will stop working - for example if you unintentionally ungrouped it and/or deleted an element of if.

Also note that you can't just copy a datagrid from one stack to another - it requires a behaviour substack with the same data to be recreated in the target stack. You can copy to the same stack (as the behaviour substack already exists), but the 2 grids will be linked (although I think can store separate data).
If your intention is just to back up data, you're better off storing the dgText or dgData of the datagrid.

Stam

[CAsba]

Hi all,
Stam, the not-start problem was after the start centre was showing, clicking on the stack resulted in the whirly wheel showing for less than a second and nothing else happened.
I discovered this weekend that if I shut down LC using Ctrl-Alt-Del, I could re-start it, when it wouldn't re-start if I shut it down using >File>Close. So, I'm back in business, problem solved. Evidently, Ctrl-Alt-Del worked on something (unknown) and righted it. I also got the DG to show its data by copying the data into it from another (backup) dg.
Many thanks, all, for your concern.

[stam]

Glad you got it sorted but it feels unsatisfactory not finding a cause. Ctrl-Alt-Del isn’t a an explanation - other perhaps that there was something wrong with your stack and you forced it to load its backup (on windows LC creates a temp backup in the same location and with the same name but prefixing this with “~”. It deletes it on shutdown but it states in place on crash).

The fact that LC shows you the start centre but crashes on trying to open the stack means
1. LC itself is starting up fine
2. The problem is within your code (usually a preopen or open handler). And this may be a recursion issue (ie a circular argument that keeps running a handler repeatedly).

The way to tackle this is after you launch LC and before you open your stack, you disable messages and then open your stack.
This prevents your preopen/open handlers from running automatically. You can then set breakpoints in your code to step through it to step through it and correct the issue.


Anyway it sounds academic as your issue is sorted - just mentioning this in case you have a similar problem in the future…


Best regards
Stam

[FourthWorld]

File -> Close or File -> Exit?

[CAsba]

File -> Close