c# - Illegal Characters In Path Mystery -

this question might quite localised, need opinion on i'm doing wrong here. how can passing illegal characters in path temporary file when @ every stage of process, appears fine , normal?

i'm getting this:

system.reflection.targetinvocationexception: exception has been thrown target of invocation. ---> system.argumentexception: illegal characters in path. 

when passing this:

"c:\documents , settings\<username>\local settings\temp\1\tmp1e0.tmp"

to this:

xmldocument doc = new xmldocument(); doc.load(<above string>); 

the file exists in location specified (i've checked during execution) although system.io.file.exists thinks otherwise; cannot see obvious. there try work around it?

more code available upon request:

req1: how path being declared?

try {     session.tempconfigdir = system.io.path.gettempfilename();     //all work done temp file happens within form     form currentform = new welcomedialog(session);     dialogresult dr = currentform.showdialog(); } {     file.delete(session.tempconfigdir); } 

the session variable passed around various locations, not altered.

req2: are using <username>?

no, edited out. it's valid windows username.

req3: what debugging?

this happening within installer (which difficult physically debug) above string example can logs, valid username, of course.

req4: more code on how it's used?

i'm adding wix tag because involves wix3.7.

basic data holding class:

public class sessionstate {     //<other properties>     public string tempconfigdir { get; set; }      public sessionstate()     {         //setting of properties     } } 

from within form:

//stringbuilder arguments installerargs.append("\" tempconfigdir=\""); installerargs.append(m_session.tempconfigdir); //... process p = process.start("msiexec", installerargs.tostring()); p.waitforexit(); 

append: part missed form:

//it's grabbing web.config existing install //and copying on temp file, not changing location or name. file.copy(m_session.installdir + dir_web_config, m_session.tempconfigdir, true); 

from within wix3.7's msi:

<property id="tempconfigdir" value="unset" /> 

...

<custom action="ca_installuica.setprop" after="startservices">not installed</custom> <custom action="ca_installuica" after="ca_installuica.setprop">not installed</custom> 

...

<customaction id="ca_installuica.setprop" property="ca_installuica" value="rcswebdir=[mcwsvdir];webdir=[webappvdir];installtype=notransaction;targetdir=[installdir];interaction=[interaction];tempconfigdir=&quot;[tempconfigdir]&quot;;" /> 

from within custom action uses it:

wz.autosettings.tempconfiglocation = session.customactiondata["tempconfigdir"]; //where above string passed out session.log(wz.autosettings.tempconfiglocation); //the rest of code uses above , exception thrown 

req5: do change tempconfigdir variable something.xml?

no, copy xml file on exact name/directory that's supplied (including .tmp).

req6: are sure it's happening on .load()?

yes, i've logged each side of line , hit first 1 when executing.

this line seems suspect:

<customaction id="ca_installuica.setprop" property="ca_installuica" value="rcswebdir=[mcwsvdir];webdir=[webappvdir];installtype=notransaction;targetdir=[installdir];interaction=[interaction];tempconfigdir=&quot;[tempconfigdir]&quot;;" /> 

the portion quoting path appears doubling quotes, producing exception:

tempconfigdir="[tempconfigdir]" 

remove &quote; wrapping deliver actual path:

tempconfigdir=[tempconfigdir]