Try the following, if it doesn't work, please send us a ZIP file containing your .LBK data file OR send your recent backup (.BAK) file for review.
-Click start...run and type in REGEDIT, press okay to get into the registry editor
-Expand HKEY_CURRENT_USER
-Expand Software
-Expand VB and VBA Program Settings
-Find any entries on the left with "Logbook Pro" in the text, right-click and delete each one
-Close the registry editor
-Uninstall Logbook Pro from the Windows Control Panel Add/Remove programs area
-Reboot
-Rename C:\Program Files\Logbook Pro to C:\Program Files\Logbook Pro-OLD
-Reinstall 1.10.26 after downloading from the URL below
http://download.logbookpro.com/lbproNoMSI.exe
For tips on installing to Vista, please see:
http://www.nc-software.com/?kb=62