Symptoms
After migrating forms from Planning 9.3.1 to 11.1.2.1, unable to open some Planning forms from within Planning web, the same forms open fine from within Workspace.Cause
Ampersand character "&" present in the name of folder or in the name of the form.Solution
1. Login to Planning web as an administrator.2. Edit the form/folder which has Ampersand character "&" in the name.
3. Remove Ampersand character "&" from the Planning form/folder name.
4. Re-test the issue.