[Idahosnowdragon]

Installed version 9.7 and the eviewer won't open some books.

calibre, version 9.7.0
ERROR: Loading book failed: Failed to open the book at F:\Data\Books\Libraries\Kens Library\Kevin J. Anderson\Working Stiff (3234)\Working Stiff - Kevin J. Anderson.epub. Click "Show details" for more info.

Failed to convert book: F:\Data\Books\Libraries\Kens Library\Kevin J. Anderson\Working Stiff (3234)\Working Stiff - Kevin J. Anderson.epub with error:

Uninstalled 9.7 and installed 7.8 everything works, upgraded back to 9.7 and it fails to open some books, seems to be able to open books that were opened in 7.8.

Ran calibre-debug -w

QPA platform: windows
devicePixelRatio: 1.0
logicalDpi: 96.0 x 96.0
physicalDpi: 58.05714285714285 x 58.615384615384606
ApplicationPaletteChange event ignored
Using calibre Qt style: True
ApplicationPaletteChange event received
Sandboxing disabled by user.
[18656:9864:0429/005920.721:ERROR:cache_util_win.cc(20)] Unable to move the cache: Access is denied. (0x5)
[18656:21644:0429/005920.721:ERROR:cache_util_win.cc(20)] Unable to move the cache: Access is denied. (0x5)
[18656:14216:0429/005920.722:ERROR:cache_util_win.cc(20)] Unable to move the cache: Access is denied. (0x5)
[18656:544:0429/005920.742:ERROR:disk_cache.cc(216)] Unable to create cache
[18656:544:0429/005920.742:ERROR:gpu_disk_cache.cc(711)] Gpu Cache Creation failed: -2
[18656:544:0429/005920.742:ERROR:disk_cache.cc(216)] Unable to create cache
[18656:544:0429/005920.742:ERROR:gpu_disk_cache.cc(711)] Gpu Cache Creation failed: -2
[18656:544:0429/005920.742:ERROR:disk_cache.cc(216)] Unable to create cache
[18656:544:0429/005920.742:ERROR:gpu_disk_cache.cc(711)] Gpu Cache Creation failed: -2
[18656:8704:0429/005920.751:ERROR:gpu_channel_manager.cc(966)] Failed to create GLES3 context, fallback to GLES2.
[18656:8704:0429/005920.751:ERROR:gpu_channel_manager.cc(977)] ContextResult::kFatalFailure: Failed to create shared context for virtualization.
[18656:8704:0429/005920.751:ERROR:gpu_channel_manager.cc(966)] Failed to create GLES3 context, fallback to GLES2.
[18656:8704:0429/005920.751:ERROR:gpu_channel_manager.cc(977)] ContextResult::kFatalFailure: Failed to create shared context for virtualization.
[1.610] bridge ready
[1.736] iframe ready

Got this.

Any ideas?