Getting a database error

If I activate Mappress I get a database error:

[Tablespace for table "'mydomain_wp'.'wp_mappress_maps'" exists. Please DISCARD the tablespace before IMPORT]
CREATE TABLE wp_mappress_maps ( mapid INT NOT NULL AUTO_INCREMENT PRIMARY KEY, obj LONGTEXT) CHARACTER SET utf8;

We were using Mappress before with no problems. When I view the database in phpMyAdmin there is no table called “wp_mappress_maps”. There is a table called “wp_mappress_posts” and I have tried dropping that table, but when I activate the plugin again I get the same database error again.