All mailboxes erroneously show "no messages found" You can go though the entire list on the left and all come up with the "no messages found" screen. The only solution is to restart/ This occurs after it has been working fine for hours, often after moving one of a few messages out of Inbox. Name Thunderbird Version 128.5.0esr Build ID 20241125170630 Distribution ID Update Folder C:\ProgramData\Mozilla-1de4eec8-1241-4177-a864-e594e8d1fb38\updates\66024440CA2A2D8C Update History Update Channel esr User Agent Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Thunderbird/128.5.0 OS Windows_NT 10.0 19045 Application Binary E:\Program Files (x86)\Mozilla Thunderbird\thunderbird.exe Profile Folder (Local drive) Build Configuration Thunderbird 128.5.0esr - 20241125170630 Thunderbird source https://hg.mozilla.org/releases/comm-esr128/rev/5aa787475f1ff704f48d561dd2ba209b092f8336 Platform source https://hg.mozilla.org/releases/mozilla-esr128/rev/68352da82b95d7114af99b268c179195fd2fead0 The latest information on building Thunderbird can be found at https://developer.thunderbird.net/. Build platform Target i686-pc-mingw32 Build tools Compiler Version Compiler flags /builds/worker/fetches/clang/bin/clang-cl -fms-compatibility-version=19.39 -Xclang -std=gnu99 -m32 -Xclang -ivfsoverlay -Xclang /builds/worker/fetches/vs/overlay.yaml 18.1.5 -fcrash-diagnostics-dir=/builds/worker/artifacts -D_HAS_EXCEPTIONS=0 -Gy -Zc:inline -arch:SSE2 -Gw /builds/worker/fetches/clang/bin/clang-cl -fms-compatibility-version=19.39 -Xclang -std=c++17 -m32 -Xclang -ivfsoverlay -Xclang /builds/worker/fetches/vs/overlay.yaml 18.1.5 -GR- -fcrash-diagnostics-dir=/builds/worker/artifacts -TP -Zc:sizedDealloc- -D_HAS_EXCEPTIONS=0 -Gy -Zc:inline -arch:SSE2 -Gw -D_SILENCE_TR1_NAMESPACE_DEPRECATION_WARNING -Z7 -O2 -Oy- /builds/worker/fetches/rustc/bin/rustc 1.78.0 Configure options MOZ_AUTOMATION=1 --enable-project=comm/mail --target=i686-pc-windows-msvc MOZILLA_OFFICIAL=1 --enable-update-channel=esr MOZBUILD_STATE_PATH=/builds/worker/.mozbuild MOZ_FETCHES_DIR=/builds/worker/fetches ENABLE_CLANG_PLUGIN=1 --enable-js-shell --enable-rust-simd UPX=/builds/worker/fetches/upx-3.95-win64/upx.exe --enable-official-branding Cache Use about:cache Information about the Network Cache Storage Service memory Number of entries: 4 Maximum storage size: 200000 KiB Storage in use: 3 KiB Storage disk location: none, only stored in memory List Cache Entries disk Number of entries: 450 Maximum storage size: 153600 KiB Storage in use: 26921 KiB Storage disk location: F:\Cache\cache2 Performance about:processes Registered Service Workers about:serviceworkers Third-party Modules about:third-party Launcher Process Enabled Multiprocess Windows 0/0 Fission Windows 0/0 Enabled by default Remote Processes 2 Enterprise Policies Inactive Google Location Service Key Missing Google Safebrowsing Key Missing Mozilla Location Service Key Missing Safe Mode false Memory Size (RAM) 47.8 GB Disk Space Available 21.7 GB