im getting this message when i try to query 2 lists against each other:

"the wizard is unable to open your query in datasheet mode, possibly because another user has a source table open in exclusive mode. your query will be opened in design view"

the first list is one ive used many times before in other queries. the second one is a new one that i ran a couple queries before with no problems. but when i run them against each other, i keep getting that message. i tried rebooting & even did everything from scratch without having to recreate data. still nothing. i also tried just copying the data from the spreadsheets on to new spreadsheets & also directly into a table. it still doesnt work. i think it might be something wrong with the data because i was able to run these queries before.

can anyone help?