Eric is correct about the %. In Access you use * and in SQL you use a %. What you might be missing is the single quotes around your supplied variable.

e.g.
"SELECT * FROM tblMyTable LIKE " & strVariableName & "*;"

is different from:

"SELECT * FROM tblMyTable LIKE '" & strVariableName & "*';"

It sounds like your error message is interpreting the * as a SQL command because it is not inside quotes. So if you are using SQL, make sure you use a %, and if your field is a character/string type, ensure you use the single quotes.