build: Remove lingering Windows registry & shortcuts (#32132 follow-up) #33422

1. 
   hodlinator commented at 7:57 am on September 18, 2025: contributor

   Problem

   Prior to fb2b05b1259d3e69e6e675adfa30b429424c7625 / #32132 we installed using paths with an extra " (64-bit)"-suffix. Installing a version including that commit on top of a version that does not results in 2 entries in the “Installed apps” list. Both of them end up running the same C:\Program Files\Bitcoin\uninstall.exe. However, only one of the entries is removed by the uninstaller. The left over registry entry will now point to an executable that no longer exists and fail to work.

   Removing the left over “Installed apps” entry on master currently requires the user to manually remove the Windows Registry entries (or run the correct old/new installer to ensure the uninstaller exists again).

   Solution

   This PR automates removal of old entries (& shortcuts) when installing the new version.

   Disclaimer

   Not an NSIS expert - confirmed that added deletion commands work without causing any visible errors both when prior items exist and when they don’t.

   Post-merge edit: Issue was initially reported by @hebasto in #32132 (comment)

2. DrahtBot added the label Build system on Sep 18, 2025
3. 
   DrahtBot commented at 7:57 am on September 18, 2025: contributor

   The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

   Code Coverage & Benchmarks

   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/33422.

   Reviews

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   Type	Reviewers
   ACK	hebasto, achow101

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4. hodlinator renamed this:
   build: Clean lingering Windows registry & shortcuts (#32132 follow-up)
   build: Remove lingering Windows registry & shortcuts (#32132 follow-up)
   on Sep 18, 2025
5. achow101 added this to the milestone 30.0 on Sep 18, 2025
6. 
   hodlinator commented at 8:07 pm on September 18, 2025: contributor

   Parallel uninstall entries:

   Error when trying to uninstall the second entry after the first one has already been uninstalled:

7. in share/setup.nsi.in:125 in 1a4ad0ae50 outdated

   119+    Delete /REBOOTOK "$SMPROGRAMS\$StartMenuGroup\Uninstall $(^Name) (64-bit).lnk"
   120+    Delete /REBOOTOK "$SMPROGRAMS\$StartMenuGroup\$(^Name) (64-bit).lnk"
   121+    DeleteRegValue HKCU "${REGKEY} (64-bit)" StartMenuGroup
   122+    DeleteRegValue HKCU "${REGKEY} (64-bit)" Path
   123+    DeleteRegKey /IfEmpty HKCU "${REGKEY} (64-bit)\Components"
   124+    DeleteRegKey /IfEmpty HKCU "${REGKEY} (64-bit)"
   

   ---

   ---

   

   hodlinator commented at 8:12 pm on September 18, 2025:

   Apart from the added (64-bit) suffix, these are copied from the uninstaller sections below, excluding items which would not originally have had the suffix.
8. 
   fanquake commented at 9:00 pm on September 18, 2025: member

   cc @sipsorcery
9. 
   achow101 commented at 9:23 pm on September 18, 2025: member

   ACK 1a4ad0ae501d15f77b1601ace3e1a1c8bf440dd6

   Tested on Windows 11, and it appears to correctly remove the old (64-bit) uninstall entry.

10. luke-jr referenced this in commit ba0bd1d3a9 on Sep 19, 2025
11. 
    hebasto commented at 12:50 pm on September 19, 2025: member

    Concept ACK. @hodlinator Thank you!

    Another alternative is to ask the user to uninstall any previous installation before installing a new one, but this is suboptimal.

12. 
    hebasto commented at 2:20 pm on September 19, 2025: member

    I suggest the following patch:

     0--- a/share/setup.nsi.in
     1+++ b/share/setup.nsi.in
     2@@ -118,10 +118,12 @@ Section -post SEC0001
     3     DeleteRegKey HKCU "SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\$(^Name) (64-bit)"
     4     Delete /REBOOTOK "$SMPROGRAMS\$StartMenuGroup\Uninstall $(^Name) (64-bit).lnk"
     5     Delete /REBOOTOK "$SMPROGRAMS\$StartMenuGroup\$(^Name) (64-bit).lnk"
     6+    Delete /REBOOTOK "$SMPROGRAMS\$StartMenuGroup\Bitcoin Core (testnet, 64-bit).lnk"
     7     DeleteRegValue HKCU "${REGKEY} (64-bit)" StartMenuGroup
     8     DeleteRegValue HKCU "${REGKEY} (64-bit)" Path
     9     DeleteRegKey /IfEmpty HKCU "${REGKEY} (64-bit)\Components"
    10     DeleteRegKey /IfEmpty HKCU "${REGKEY} (64-bit)"
    11+    RMDir /r /REBOOTOK $INSTDIR\doc
    12 SectionEnd
    13 
    14 # Macro for selecting uninstaller sections
    

    It additionally clears lingering artifacts from older versions and enables a clean uninstall on systems with a long upgrade history.

    See:

    • #25809
    • https://github.com/bitcoin/bitcoin/pull/26334
13. build(windows): Remove lingering registry entries and shortcuts upon install

    Prior releases installed using these paths. Especially annoying was that the lingering registry entry for the uninstaller would show up as "Bitcoin Core (64-bit)" besides the current "Bitcoin Core" entry in the list of installed programs, and whichever was uninstalled last would fail to work as they would default to the same install directory.

    79752b9c0b
14. hodlinator force-pushed on Sep 19, 2025
15. 
    hebasto commented at 2:50 pm on September 19, 2025: member

    What about RMDir /r /REBOOTOK $INSTDIR\doc part I mentioned in #33422#pullrequestreview-3245114592?
16. 
    hodlinator commented at 2:51 pm on September 19, 2025: contributor

    Another alternative is to ask the user to uninstall any previous installation before installing a new one, but this is suboptimal.

    Yup. I wish NSIS would keep exact track of previously installed files in the registry with checksums and allowed one to diff against the new files.

    I suggest the following patch: … It additionally clears lingering artifacts from older versions and enables a clean uninstall on systems with a long upgrade history.

    See:

    * [#25809](/bitcoin-bitcoin/25809/)
    
    * [#26334](/bitcoin-bitcoin/26334/)
    

    Aha, I have been wondering why we don’t provide at least some of the docs with the install (doc/reduce-memory.md comes to mind as appropriate for node operators). I’m worried users might modify/add files under docs so I skipped that part for now. (Considered adding it without /r to only delete empty directories but that felt quite pointless).

    Added comments for which commits the corresponding files where lingering from.

17. hebasto approved
18. 
    hebasto commented at 2:53 pm on September 19, 2025: member

    ACK 79752b9c0b6bd9b2203ac98d28dd67734050c14a.
19. DrahtBot requested review from achow101 on Sep 19, 2025
20. 
    achow101 commented at 8:50 pm on September 19, 2025: member

    ACK 79752b9c0b6bd9b2203ac98d28dd67734050c14a
21. hebasto merged this on Sep 19, 2025
22. hebasto closed this on Sep 19, 2025

    ---

23. hebasto added the label Needs backport (30.x) on Sep 19, 2025
24. fanquake referenced this in commit 57ebe3b132 on Sep 20, 2025
25. 
    fanquake commented at 9:08 am on September 20, 2025: member

    Backported to 30.x in #33424.
26. fanquake removed the label Needs backport (30.x) on Sep 20, 2025

Contributors
hodlinator DrahtBot fanquake achow101 hebasto

Review Requested
achow101

Labels
Build system

Milestone
30.0