SQL & PL/SQL

I am a newbie when it comes to working with tables, so any help would be greatly appreciated.

I am getting the following error when I run my SQL statement:
ORA-01417: a table may be outer joined to at most one other table

This is my SQL statement:

select p.l_name as Last,
p.f_name as First,
r.major_skills as Description,
r.resume_title as ResumeTitle,
r.objective as Objective,
p.user_id as UserID
from project_user p, resume_qual r, clearance c,
hardware_experience h, software_experience s,
experience e, industry_experience i, software_link b,
hardware_link a, industry_link d
where e.resume_id = r.resume_id (+)
and d.industry_exp_id = i.industry_exp_id (+)
and a.hardware_exp_id = h.hardware_exp_id (+)
and b.software_exp_id = s.software_exp_id (+)
and a.resume_id = r.resume_id (+)
and b.resume_id = r.resume_id (+)
and d.resume_id = r.resume_id (+)
and c.resume_id = r.resume_id (+)
and r.user_id = p.user_id

Thanks!!