"unserialize" error

Gallery version (not just "2"): 2.1.1
PHP version (e.g. 4.3.11):
PHPInfo Link (see FAQ):
Webserver (e.g. Apache 1.3.33):
Database (e.g. MySql 4.0.11): mysql3
Activated toolkits (e.g. NetPbm, GD): core only
Operating system (e.g. Linux): Windows
Browser (e.g. Firefox 1.0): IE

After seemingly installing the core module only, I get the following errors when I attempt to go to the Gallery page:

Notice: unserialize() [function.unserialize]: Error at offset 5 of 97 bytes in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryDataCache.class on line 800

Notice: unserialize() [function.unserialize]: Error at offset 18 of 263 bytes in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryTheme.class on line 744

Warning: Invalid argument supplied for foreach() in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryTheme.class on line 747

Notice: unserialize() [function.unserialize]: Error at offset 18 of 60 bytes in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryTheme.class on line 744

Warning: Invalid argument supplied for foreach() in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryTheme.class on line 747

Notice: unserialize() [function.unserialize]: Error at offset 18 of 107 bytes in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryTheme.class on line 744

Warning: Invalid argument supplied for foreach() in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryTheme.class on line 747

Notice: unserialize() [function.unserialize]: Error at offset 5 of 97 bytes in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryDataCache.class on line 800

Notice: unserialize() [function.unserialize]: Error at offset 5 of 97 bytes in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryDataCache.class on line 800

Notice: unserialize() [function.unserialize]: Error at offset 5 of 97 bytes in C:\Sites\Single33\huntmark\webroot\renegades\modules\core\classes\GalleryDataCache.class on line 800