Same problem here.
I copied my old 1.5 database, installed a new instance of moodle16 and changed config.php to point to this copied database.
After connecting as the administrator, I get some upgrading activity and get stuck with errors when updating the book module:
================================
(my
sql): CREATE TABLE mdl_book ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, course INT(10) UNSIGNED NOT NULL DEFAULT '0', name VARCHAR(255) NOT NULL DEFAULT '', summary TEXT NOT NULL DEFAULT '', numbering TINYINT(4) UNSIGNED NOT NULL DEFAULT '0', disableprinting TINYINT(2) UNSIGNED NOT NULL DEFAULT '0', customtitles TINYINT(2) UNSIGNED NOT NULL DEFAULT '0', timecreated INT(10) UNSIGNED NOT NULL DEFAULT '0', timemodified INT(10) UNSIGNED NOT NULL DEFAULT '0', PRIMARY KEY (id)) COMMENT='Defines book' 1050: Table 'mdl_book' already exists
adodb_mysql._execute(CREATE TABLE mdl_book ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, course INT(10) UNSIGNED NOT NULL DEFAULT '0', name VARCH..., false) % line 853, file: adodb.inc.php
adodb_mysql.execute(CREATE TABLE mdl_book ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, course INT(10) UNSIGNED NOT NULL DEFAULT '0', name VARCH...) % line 49, file: datalib.php
execute_sql(CREATE TABLE mdl_book ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, course INT(10) UNSIGNED NOT NULL DEFAULT '0', name VARCH...) % line 193, file: datalib.php
modify_database(D:\apache2\htdocs\moodle16/mod/book_16/db/mysql.sql) % line 224, file: adminlib.php
upgrade_activity_modules(
http://respir.med.unisi.it:8008/moodle16/admin/index.php) % line 229, file: index.php
Error
(mysql): CREATE TABLE mdl_book_chapters ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, bookid INT(10) UNSIGNED NOT NULL DEFAULT '0', pagenum INT(10) UNSIGNED NOT NULL DEFAULT '0', subchapter TINYINT(2) UNSIGNED NOT NULL DEFAULT '0', title VARCHAR(255) NOT NULL DEFAULT '', content LONGTEXT NOT NULL DEFAULT '', hidden TINYINT(2) UNSIGNED NOT NULL DEFAULT '0', timecreated INT(10) UNSIGNED NOT NULL DEFAULT '0', timemodified INT(10) UNSIGNED NOT NULL DEFAULT '0', importsrc VARCHAR(255) NOT NULL DEFAULT '', PRIMARY KEY (id)) COMMENT='Defines book_chapters' 1050: Table 'mdl_book_chapters' already exists
adodb_mysql._execute(CREATE TABLE mdl_book_chapters ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, bookid INT(10) UNSIGNED NOT NULL DEFAULT '0', p..., false) % line 853, file: adodb.inc.php
adodb_mysql.execute(CREATE TABLE mdl_book_chapters ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, bookid INT(10) UNSIGNED NOT NULL DEFAULT '0', p...) % line 49, file: datalib.php
execute_sql(CREATE TABLE mdl_book_chapters ( id INT(10) UNSIGNED NOT NULL AUTO_INCREMENT, bookid INT(10) UNSIGNED NOT NULL DEFAULT '0', p...) % line 193, file: datalib.php
modify_database(D:\apache2\htdocs\moodle16/mod/book_16/db/mysql.sql) % line 224, file: adminlib.php
upgrade_activity_modules(
http://respir.med.unisi.it:8008/moodle16/admin/index.php) % line 229, file: index.php
Error
(mysql): INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'update', 'book', 'name') 1062: Duplicate entry 'book-update' for key 2
adodb_mysql._execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'update', 'book', 'name'), false) % line 853, file: adodb.inc.php
adodb_mysql.execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'update', 'book', 'name')) % line 49, file: datalib.php
execute_sql(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'update', 'book', 'name')) % line 193, file: datalib.php
modify_database(D:\apache2\htdocs\moodle16/mod/book_16/db/mysql.sql) % line 224, file: adminlib.php
upgrade_activity_modules(
http://respir.med.unisi.it:8008/moodle16/admin/index.php) % line 229, file: index.php
Error
(mysql): INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view', 'book', 'name') 1062: Duplicate entry 'book-view' for key 2
adodb_mysql._execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view', 'book', 'name'), false) % line 853, file: adodb.inc.php
adodb_mysql.execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view', 'book', 'name')) % line 49, file: datalib.php
execute_sql(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view', 'book', 'name')) % line 193, file: datalib.php
modify_database(D:\apache2\htdocs\moodle16/mod/book_16/db/mysql.sql) % line 224, file: adminlib.php
upgrade_activity_modules(
http://respir.med.unisi.it:8008/moodle16/admin/index.php) % line 229, file: index.php
Error
(mysql): INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view all', 'book', 'name') 1062: Duplicate entry 'book-view all' for key 2
adodb_mysql._execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view all', 'book', 'name'), false) % line 853, file: adodb.inc.php
adodb_mysql.execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view all', 'book', 'name')) % line 49, file: datalib.php
execute_sql(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'view all', 'book', 'name')) % line 193, file: datalib.php
modify_database(D:\apache2\htdocs\moodle16/mod/book_16/db/mysql.sql) % line 224, file: adminlib.php
upgrade_activity_modules(
http://respir.med.unisi.it:8008/moodle16/admin/index.php) % line 229, file: index.php
Error
(mysql): INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'print', 'book', 'name') 1062: Duplicate entry 'book-print' for key 2
adodb_mysql._execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'print', 'book', 'name'), false) % line 853, file: adodb.inc.php
adodb_mysql.execute(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'print', 'book', 'name')) % line 49, file: datalib.php
execute_sql(INSERT INTO mdl_log_display (module, action, mtable, field) VALUES ('book', 'print', 'book', 'name')) % line 193, file: datalib.php
modify_database(D:\apache2\htdocs\moodle16/mod/book_16/db/mysql.sql) % line 224, file: adminlib.php
upgrade_activity_modules(
http://respir.med.unisi.it:8008/moodle16/admin/index.php) % line 229, file: index.php
Error
book_16 tables could NOT be set up successfully!
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Piersante