I am working in a 64-bit Windows 7 environment and running a 32-bit version of LabVIEW.
I need to link up a specific instrument to LabVIEW, using a LabVIEW library which was given to me by the company that made the instrument. The library includes calls to a couple 32-bit DLL files which were also given to me by the company.
LabVIEW is having trouble reading those DLL files, and whenever I try to open a file I get a popup message that says "Error loading DLL". Is this because of a 32-bit/64-bit incompatibility, or is it due to something else altogether ?
Thanks,
Check the DLL in the dependency walker, there must be a DLL dependency problem.
You should be able to call at 32 bit DLL from 32 bit LabVIEW in a 64 bit OS. I believe the issue is something else.
Related
I have a LV program that calls an external library via wrapper functions that I downloaded via VI package manager (libxml2). This program works fine on computer A (Win7, LV2015 32-bit). Since it is meant to be portable, I have installed it on various computers (Win7) where it runs well, except for computer B. There, it throws an Error 1097 when calling the external library. The libxml2 package is obviously installed and I can see it on the Functions palette. Could it be due to the differing versions of Windows, or due to conflicts between Labview 32- and 64-bit? I open and run my program with LV 32-bit.
Computer A:
Labview 2015 (32-bit)
Windows 7
Computer B:
Labview 2015 (32-bit)
and Labview 2015 (64-bit)
Windows 10
It is very likely that the call parameters to the dll need to be changed between the 32bit and 64bit labview vi, this is indicative of the error 1097. If you have pointers or need to reserve memory these can have different size between the 64bit and 32bit variants.
For more help code needs to be shown also a more detailed error description if that is provided.
I was able to solve the problem: probably, there were race conditions and sometimes the DLL was getting illogical random input. It had nothing to do with the system.
I have a huge application that uses external components.
Some of these external components are not actively maintained.
I can interop them, but they are then still win32 components.
I hope I expressed myself correctly.
Can I then still compile my application for 64 bit, or am I doomed to staying at 32 bit because my external components do not support 64?
Thank you!
it is just like you said. 64-bit application can only have 64-bit components. To have 32-bit code, it has to be compiled to 32-bits.
I had this problem a lot of times with Crystal Reports and Microsoft Office. Office already exists in 64, but still these applications are doomed because of 32-bit Crystal Reports, because there isn't another.
a few years ago I was a Windows application developer.
In the last years I am dealing with kernel and system software.
Now:
I have a customer who tells me that he has a 64bit C/C++ application with
specific functionality. This functionality is a dongle request
and comes from an external 32bit dll.
He says that this functionality is given although I can not see the
DLL in memory.
If I delete the DLL, the 64bit application is still loaded.
That means the 32bit DLL is somehow a static part of the 64bit application.
Can that be true nowadays?
And if so how can I achieve that with Visual Studio?
Best regards
Burkhardt
Based on what I have found on StackOverflow.com it is not possible to load a 32-bit DLL from a 64-bit application (or vice versa) dynamically or statically. There are however a few workarounds.
See the following:
https://stackoverflow.com/a/12938217/184528
https://stackoverflow.com/a/5720902/184528
https://stackoverflow.com/a/11642165/184528
Is it possible to load a 64-bit dll into a 32-bit process ?
Generally speaking, I know it can not happen.
Yet, maybe there are some exceptions ?
No, and neither a 64-bit process can load a 32-bit DLL.
If you're on a 64 bit OS, you can load the DLL in a 64-bit process and have it communicate with your 32-bit process through IPC.
If you're on a 32 bit OS, you're out of luck.
In .NET, it is possible to load a 64-bit DLL into a 32-bit process for reflection only. For details please check "Analyze 64-bit DLL from within T4 template in Visual Studio (32-bit) using Reflection".
I know that this is a special case, but I thought I'd add it anyway because it might help others looking for a similar solution as me.
Yes, you can load 64 code in 32 bit module. example:
vmprotect
metatrader4
above software mixed x86 and x64 in one process.
I found metatrade4 for win7 has a function it exeucte a instruction like :
jmp 0x33:0x175328
segment selector 33 is a 64bit segment. after execution this instruction, cpu will switch to 64bit mode from 32bit mode.
if you use windbg to trace some windows api on windows x64 OS, you will find similar code.
for example:
NtQueryInformationProcess
But new computer bought today at least have 4G ram. We cannot prevent using 64-bit OS to avoid problem. We must face 64-bit positively! Server 2008 R2 only have 64-bit.
Issues around EXE AnyCPU / x86, 32-bit COM / C++ dll must be handled.
Ideally compile both 32 and 64 bit COM / C++ dll.
My company has a VB6 application using Crystal Reports 7 which a client has asked to be installed on Windows 7 32 bit. It is currently installed on Windows XP 32bit SP2 machines at the client. Connection to the DB is done via ODBC to SQL Server 2000 instance on another server.
On Windows 7, the installation works fine, however when you try to open the application, the error is given.
I have looked at the following:
Registering all the dll's and ocx files using regsvr32. Some will not register as they either are registered already or the following message is given "Make sure that "[name].dll" is valid DLL or OCX file and then try again." I read this forum thread regarding this: http://social.msdn.microsoft.com/forums/en-US/vblanguage/thread/0653f685-4526-45d9-89f3-8c479a6b4c62
Monitored the opening of the application using a ProcessMonitor application to try and spot if there is a missing dll or ocx file - this does not seem to be the case.
Reviewed the application according to this list and nothing seems to be against these guidelines
I've noticed two items in the knowledge base that relate to this
http://support.microsoft.com/kb/281848 - the comdlg32.ocx bundled with the application is version 6.0.81.69 and the one in the system32 folder on the dev machine (WinXP 32 bit) is 6.1.97.82. However if this was the issue then surely it would not work currently?
http://support.microsoft.com/kb/184898 - I'm not sure how to confirm that this is the issue
Finally, due to complexities, I am not allowed to make code changes to this application. Even if I was, I'm not a VB6 programmer, just the guy who got the terribly support project! If code changes are required, then I'll have to investigate using WinXP mode.
Update: I get the same error in XP Mode. That's a Win XP with SP3 VM. This runs on a Win XP SP2 VM, is there potentially something in SP3 that would have caused this to occur? Or is it just a fact of it being XP Mode?
I got the same error but I solved by using regsvr32.exe in C:\Windows\SysWOW64.
Because we use x64 system. So if your machine is also x64, the ocx/dll must registered also with regsvr32 x64 version
The file msrdo20.dll is missing from the installation.
According to the Support Statement for Visual Basic 6.0 on Windows Vista, Windows Server 2008 and Windows 7 this file should be distributed with the application.
I'm not sure why it isn't, but my solution is to place the file somewhere on the machine, and register it using regsvr32 in the command line, eg:
regsvr32 c:\windows\system32\msrdo20.dll
In an ideal world you would package this up with the redistributable.
This download fixed my VB6 EXE and Access 2016 (using ACEDAO.DLL) run-time error 429. Took me 2 long days to get it resolved because there are so many causes of 429.
http://www.microsoft.com/en-ca/download/details.aspx?id=13255
QUOTE from link:
"This download will install a set of components that can be used to facilitate transfer of data between 2010 Microsoft Office System files and non-Microsoft Office applications"
You say it works once you install the VB6 IDE so the problem is likely to be that the components you are trying to use depend on the VB6 runtime being installed.
The VB6 runtime isn't installed on Windows by default.
Installing the IDE is one way to get the runtime. For non-developer machines, a "redistributable" installer package from Microsoft should be used instead.
Here is one VB6 runtime installer from Microsoft. I'm not sure if it will be the right version for your components:
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=7b9ba261-7a9c-43e7-9117-f673077ffb3c