Just in case it helps anyone... I have two seperate bug reports with potential fixes which also encounted an "Access Denied" in multi-company setup (but are not directly related to the bug in the description).
The first occurs when changing companies in user preferences with sales_crm (see Bug 1157484).
The second is a smaller issue with logos not displaying (see Bug 1161115) [this is what was causing the error I mentioned in comment #45]
Just in case it helps anyone... I have two seperate bug reports with potential fixes which also encounted an "Access Denied" in multi-company setup (but are not directly related to the bug in the description).
The first occurs when changing companies in user preferences with sales_crm (see Bug 1157484).
The second is a smaller issue with logos not displaying (see Bug 1161115) [this is what was causing the error I mentioned in comment #45]