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In a given parent folder, folders must not have similar names. For this, Xray does a case-insensitive check of the trimmed folder name whenever you create or rename folder. This means that these folder names would all be considered the same: "  phanTom", "phantom", "PHANTOM". Moreover, folder names must not use the following characters: "/" character", "\", apostrophe, "*".

Recommendations

• Carefully structure the hierarchy of your folders, keeping in mind that a Test may only be in a single folder. How would you organize them in your laptop if you were dealing with documents? Start by identifying the folders that you want to place at the root, and then try to drill down and create sub-folders that are relevant to you.
• If you're already using Test Sets, don't try to replicate the Test Sets model in the Test Repository because, most likely, it won't work. Again, a Test can only be part of one folder in the Test Repository; with Test Sets, a Test can belong to several Test Sets.  
• Avoid semantics when it comes to the execution phase or else, your Test Repository will get messed up. Use the proper entities, such as Test Plans (and corresponding Boards) to make planning/execution-related organization. 

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