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Dear Comunity,

I am learning and appling PowerBi, Power Query, PowePivot into my business life. This is my first post therfore it may look easy but I could not find proper solution... 

My Question is two part first part is the subject, actually I found the issue but I could not find solution;

- Our customer send every week their sales reports in excel or csv, I have just started to use PowerQuery to combine them but I realised different "table names" causes this error; some excel report sheet name are "prijmy_vydeje_skladem (005)", some prijmy_vydeje_skladem (009), etc.

When I change the name manually, The reports have the same sheet names are recognised by Power Query and not get error for that table...

How can I solve this issue first, there are 53 reports for each previous report.

I will be pleased, if you can you help.

Best regards,

Note: I use File/Folder as New Source in Power Query and locate the folder contains weekly reports