Access 365 Runtime 2605+: MsgBox in Click event stops responding (Zoom related)

Starting with Access 365 Runtime version 2605 (build 20026.20168), MsgBox called within a Click event stops responding under specific conditions. We have confirmed that the issue is related to the Access Zoom feature.

Microsoft 365 support advised us to report this issue in the community, so we are posting it here.

■ Affected Versions

• No issues confirmed prior to May 2026
• Version 2605 (build 20026.20168) and later → Affected

■ Reproduction Environment

• Access 365 Runtime
• Resolution: 1920×1080 (Full HD), Text size: 100%
• Issue does NOT reproduce at text size 125% or 150%

■ Sample File
We have a minimal sample database (Db1.accdb) that reliably reproduces this issue. It contains two forms (Form A and Form B). We can provide it on request.

■ Steps to Reproduce

1. Open the sample database → Form A opens
2. Click Button A on Form A → Form B opens
3. Click Button B on Form B → MsgBox appears (works as expected)
4. Click “No” in the MsgBox
5. Click the Close button on Form B → Form B closes
6. Click Button A on Form A again → Form B opens
7. Click Button B on Form B → MsgBox should appear, but Access stops responding instead
8. Pressing the Alt key resumes execution and MsgBox appears

Note: MsgBox displays correctly the first time Form B is opened (step 3). The issue occurs after Form B has been closed and reopened (step 7).

■ Findings

• Enabling “Disable zoom” in File → Options → Current Database prevents the issue. This option is available in version 2608 and later.
• The issue also does not occur if Form A is moved to the far left of the screen, or down to approximately the vertical center of the screen, before performing the steps.

■ Temporary Workaround for Versions 2605–2607
The “Disable zoom” option is not available in these versions. Adding the following code immediately before the MsgBox call avoids the issue:

Application.Echo False
DoEvents
Application.Echo True

However, this workaround causes side effects in some forms of our application, such as unexpected termination and unexpected parameter prompts for record sources, so it is not a suitable long-term solution.

■ Request
This issue began occurring around May 2026 in an existing application whose code has not been changed.

1. We kindly ask the Access team to investigate and fix this issue so that it does not occur when Zoom is enabled.
2. If anyone else is experiencing the same issue, please let us know. We can share the sample file on request.