difficulty to use old shapefiles with Arcmap 10.5

[ChristopheHissler]

since Arcmap 10.5 is installed on my computer the icon of all of my old shapefiles appeared with a "?" and cannot be opened anymore. THe error message is " error opening a feature class".

How could I solve this problem?

[Bo_King · Accepted solution]

Hi Christophe 

Have you tried adding the shapefiles to a new empty ArcMap session?  Some additional resources can be found at the links below.

What is a shapefile?—Help | ArcGIS for Desktop 

How to salvage a corrupt shapefile—Help | ArcGIS for Desktop 

Regards,

Bo