Forum Discussion
Office v2508 feature update (new vbe7.dll) breaks library compatibility with LTSC VL versions
Since the Jan 2026 updates, some `accde` or `mde` libraries built with the semi-annual enterprise channel (v2508, Build 19127.20484) can no longer be used with the volume-licensed version of Office LTSC (tested with the Jan 2026 release of Office 2024 LTSC VL, v2408, Build 17932.20638).
The reason for this seems obvious: The v2508 feature update contains an updated vbe7.dll. Apparently, this change is backwards-compatible (code compiled with the old dll will run with the new dll) but not completely forwards-compatible (code compiled with the new dll might not run with the old dll, even if the new RegExp class is not used).
That's a problem for us. We can't just tell our customers to upgrade, because those with an Office 2024 LTSC volume license already use the latest version available to them.
Does Microsoft consider this a bug or "by design"? If the latter, what is Microsoft's recommendation for software vendors who want to build software that runs on all currently-supported versions of Access?
We currently plan to work around this issue by installing v2502 of the semi-annual enterprise channel on our "build VMs" (32 and 64 bit) and use those to build our software. (Reverting dev machines to an old Office version is not an option for obvious security reasons.)
Repro
On a PC with v2508 or newer:
1. Create a new mylibrary.accdb with a module with the following code:
Public Function GetColorCode() As Long
GetColorCode = vbRed
End Function2. File/Save as/Create accde.
3. Copy mylibrary.accde to a PC with v2507 or older (for example, with the current version of Office 2024 LTSC volume license).
On a PC with v2507 or older:
4. Create a new database.
5. Create/Module/Tools/References
6. Add a reference to mylibrary.accde
7. Add the following code to the module:
Sub Test()
Debug.Print GetColorCode()
End Sub8. Debug/Compile
Expected result: The database compiles.
Actual result: "Compile error: Can't find project or library". The "references" window opens automatically and highlights "mylibrary".
Notes
- We are not library developers, but we are still impacted by this issue, since the software we ship consists of a (modifiable) startup mdb referencing an (unmodifiable) mde containing the business logic.
- If you want to try to reproduce this issue but don't have a volume license of Office 2024 LTSC lying around (we certainly don't), you can install a trial version with the Office Deployment Tool and the following configuration file:
<Configuration>
<Add OfficeClientEdition="64" Channel="PerpetualVL2024">
<Product ID="ProPlus2024Volume">
<Language ID="en-us" />
</Product>
</Add>
</Configuration>5 Replies
- beanisaac8Copper Contributor
It should run pretty good and there should be some new little toys in there too
I can reproduce the issue in v2507 and have just reported it to the Access team.
In fact you don't need to use the 2508+ ACCDE as a library file to trigger the error. It also occurs if you try to run the code directly from the ACCDE in 2507
As you say, it isn't clear whether this is a bug or by design. However when the move of RegEx to the VBA library was done in 2508, the documentation clearly stated that it was planned to not cause compatibility issues.
- HeinziATIron Contributor
First of all: Thank you for reproducing and forwarding the issue!
That's interesting: So far, I have not been able to reliably reproduce the issue with just the accde alone. What I tried was to (a) add a ShowColorCode method that shows the value of vbRed in a MsgBox, (b) add an AutoExec macro that calls ShowColorCode and (c) run the accde on 2507-. How did you manage to repro the issue with just the accde alone?
(This issue strongly reminds me of the ADO Windows 7 SP1 problem. Apparently, making changes to COM libraries without breaking binary compatibility is not an easy task.)
I just opened the ACCDE file directly in v2507 and ran GetColorCode from the immediate window. That triggered the error
Offhand, I can't remember the ADO Windows 7 SP1 problem you mentioned. I do remember a major issue with queries in 2003 SP3 that required a hotfix.
I also found this MS support article from 2022 on a similar issue with ACCDE files which was rapidly fixed: Error when trying to open an ACCDE/MDE file created in a different version of Access - Microsoft Support