Can't save webpart after editing with PowerShell

Question

I'm using the code below to edit the image in a webpart:

$webPartCollection = $web.GetWebPartCollection("default.aspx","Shared") 
$imagePart = $webPartCollection | Where-Object { $_.Title -eq "Site Image"}
$imagePart.ImageLink = "web/PublishingImages/myPicture.jpg"
$webPartCollection.SaveChanges($imagePart.StorageKey)

But I'm unable to save the webpart, I get the following error:

Exception calling "SaveChanges" with "1" argument(s): "Could not find file 'C:\ Users\admin\AppData\Local\Temp\2\yqvs9p_s.dll'." At line:1 char:31
+ $webPartCollection.SaveChanges <<<< ($imagePart.StorageKey)
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

What am I doing wrong?
Why is it looking for that (random) dll?

Answer 1

try something like:

$web = Get-SPWeb "http://url"
$page = $web.GetFile("default.aspx")
$wpm = $web.GetLimitedWebPartManager($page.Url, [System.Web.UI.WebControls.WebParts.PersonalizationScope]::Shared)
$wp = $wpm | Where-Object {$$_.Title -eq "Site Image"}
$wp.ImageLink = "web/PublishingImages/myPictue.jpg"
$wpm.SaveChanges($wp)