How to reproduce :
I create following tree structure :
First folder is named : Aé$çèv+tés,et (blanc) ;#agglo3 ! hgd ' gs÷b

When I try to remove a file, following error is displayed :
Caused by: org.ametys.plugins.repository.AmetysRepositoryException: Path cannot begin or end with a space character
at org.ametys.plugins.repository.AmetysObjectResolver._resolve(AmetysObjectResolver.java:434)
at org.ametys.plugins.repository.AmetysObjectResolver.resolveByPath(AmetysObjectResolver.java:270)
at org.ametys.cms.rights.CheckReadAccessAction.getAmetysObject(CheckReadAccessAction.java:126)
at org.ametys.cms.rights.CheckReadAccessAction.act(CheckReadAccessAction.java:80)
at org.apache.cocoon.components.treeprocessor.sitemap.ActTypeNode.invoke(ActTypeNode.java:125)
at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
at org.apache.cocoon.components.treeprocessor.sitemap.ActTypeNode.invoke(ActTypeNode.java:139)
at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:47)
at org.apache.cocoon.components.treeprocessor.sitemap.MatchNode.invoke(MatchNode.java:108)
at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
at org.apache.cocoon.components.treeprocessor.sitemap.PipelineNode.invoke(PipelineNode.java:143)
at org.apache.cocoon.components.treeprocessor.AbstractParentProcessingNode.invokeNodes(AbstractParentProcessingNode.java:69)
at org.apache.cocoon.components.treeprocessor.sitemap.PipelinesNode.invoke(PipelinesNode.java:93)
at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:236)
at org.apache.cocoon.components.treeprocessor.ConcreteTreeProcessor.process(ConcreteTreeProcessor.java:178)
at org.apache.cocoon.components.treeprocessor.TreeProcessor.process(TreeProcessor.java:254)
at org.apache.cocoon.components.treeprocessor.sitemap.MountNode.invoke(MountNode.java:118)
... 78 more
I cannot reproduce.
Could you please retest ? Maybe the error depends on your file's name and not parent folder's name ?
Or some fixes may have fixed this issue...