Weird issue with access 2007 runtime on Windows 7 computer

Dear experts, I have an access 2007 application that worked well on computers with Windows NT, XP, VISTA. it's a frontend accde with a backend accde. I packaged it in a sagekey installation script so that it also installs the access runtime when someone installs it. I just tried it on a computer with windows 7 and now the application is behaving very weird: I have a form with a lot of calculated controls on it. On this computer the form seems to hang whenever I recalculate the controls. sometimes it gives #ERROR as result in some controls, sometimes it gives correct results. The form keeps calculating until I move the mouse pointer over the controls it tries to calculate. Even more strange is this: if I click the windows taskbar during the calculation, the form immediately calculates correctly and all the #ERROR controls suddenly give a correct result. It feels as if the application is trapped under water until I click on any place of the windows taskbar, and then it sort of emerges.
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gstallaertAuthor Commented:
Some additional comment: Please believe me, my formulas are correct, it's not an issue of Nulls, or compact repair database, also, 'decompile database" is not one of the Ideas that I would like to see as an answer.
gstallaertAuthor Commented:
I am now going to sleep so please do not worry if I do not react immediately on your posts
Yes this is a behaviour I have seen too.
I suggest Access have sometimes a (timing?) problem with calculated controls.
I solved it by moving the logic for calculating the controls to a sub inside of the form and calling this sub whenever the fields need to recalculated.
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Scott McDaniel (Microsoft Access MVP - EE MVE )Infotrakker SoftwareCommented:
I doubt it's a timing issue, although I agree with moving the calculations to a code-based solution and only calling them when needed.

On the Windows 7 machine: Where is the database installed (i.e. what folder)?

Are you 100% sure that you are deploying or checking all needed references?

gstallaertAuthor Commented:
Ok, I'll check both your suggestions. It installs to C:\ProgramData
Scott McDaniel (Microsoft Access MVP - EE MVE )Infotrakker SoftwareCommented:
Also: It could be (a) a courrpt database or (b) a faulty installation of Access or Windows.
Sounds like the Form App and the Access Runtime are running as different applications and only as foreground tasks. Office requires opening document in a secure location. "Program Data"?

Win7 taskbar is different than previous versions. See and

You really do need to provide more detail (at one time the psychic friends network was next door but ...).  

Have you adjusted compatibility of the executable? Win7 does tighten security, are all parts of the application running in the same security context?

You didn't say you clicked on the application on the taskbar. You said that you clicked on the taskbar itself. This brings the taskbar into the foreground. Are you running this application as a tray applet? Active Desktop context? If you move mouse over app in toolbar, is the preview running or dormant?

Both Win7 and Vista are NT6 codebase. Win7 includes some optional  Vista features such as Windows Sidebar and IE8, so you might still see this in Vista. Taskbar originally developed as VB/ActiveX; rogue VB programs messed with clock in Systray.

Have you tried running the App in Safe mode? You said database was local?

One runtime issue resolution said to change extension from accde to accdb.

gstallaertAuthor Commented:
Thanks for these suggestions. Please allow me some time to test it.
How do I run the app in safe mode?( It's a runtime access application, so user can't access any of the options, which is what I want)
Press F8 function key on boot (between Bios messages and Windows boot messages; choose safe mode with networking.
Scott McDaniel (Microsoft Access MVP - EE MVE )Infotrakker SoftwareCommented:
<Root>\Program Data is a folder on Windows 7 machines, and can be used to store read/write data (like an Access database).

You should not have to run your app in Safe mode, and I'm sure your users would not really like to reboot their machine in order to run your application.

Again: Make sure that your Office/Windows installs are fully up to date.

Does this machine also have other versions of Office installed? If so, then understand that you should only run ONE version of Access at a atime.

Finally, you may simply have a bad/faulty installation of the Runtime. Have you tried uninstalling and reinstalling the entire setup?

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gstallaertAuthor Commented:
Thanks for all these suggestions.I have not had the possibility yet to test this on the problematic computer but I appreciate all these answers
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